Attempt to avoid specifying BlockHashCount for different mocking::{MockBlock, MockBlockU32, MockBlockU128} (#4543)

While doing some migration/rebase I came in to the situation, where I
needed to change `mocking::MockBlock` to `mocking::MockBlockU32`:
```
#[derive_impl(frame_system::config_preludes::TestDefaultConfig)]
impl frame_system::Config for TestRuntime {
	type Block = frame_system::mocking::MockBlockU32<TestRuntime>;
	type AccountData = pallet_balances::AccountData<ThisChainBalance>;
}
```
But actual `TestDefaultConfig` for `frame_system` is using `ConstU64`
for `type BlockHashCount = frame_support::traits::ConstU64<10>;`
[here](https://github.com/paritytech/polkadot-sdk/blob/master/substrate/frame/system/src/lib.rs#L303).
Because of this, it force me to specify and add override for `type
BlockHashCount = ConstU32<10>`.

This PR tries to fix this with `TestBlockHashCount` implementation for
`TestDefaultConfig` which supports `u32`, `u64` and `u128` as a
`BlockNumber`.

### How to simulate error
Just by removing `type BlockHashCount = ConstU32<250>;`
[here](https://github.com/paritytech/polkadot-sdk/blob/master/substrate/frame/multisig/src/tests.rs#L44)
```
:~/parity/olkadot-sdk$ cargo test -p pallet-multisig
   Compiling pallet-multisig v28.0.0 (/home/bparity/parity/aaa/polkadot-sdk/substrate/frame/multisig)
error[E0277]: the trait bound `ConstU64<10>: frame_support::traits::Get<u32>` is not satisfied
   --> substrate/frame/multisig/src/tests.rs:41:1
    |
41  | #[derive_impl(frame_system::config_preludes::TestDefaultConfig)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `frame_support::traits::Get<u32>` is not implemented for `ConstU64<10>`
    |
    = help: the following other types implement trait `frame_support::traits::Get<T>`:
              <ConstU64<T> as frame_support::traits::Get<u64>>
              <ConstU64<T> as frame_support::traits::Get<std::option::Option<u64>>>
note: required by a bound in `frame_system::Config::BlockHashCount`
   --> /home/bparity/parity/aaa/polkadot-sdk/substrate/frame/system/src/lib.rs:535:24
    |
535 |         type BlockHashCount: Get<BlockNumberFor<Self>>;
    |                              ^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Config::BlockHashCount`
    = note: this error originates in the attribute macro `derive_impl` which comes from the expansion of the macro `frame_support::macro_magic::forward_tokens_verbatim` (in Nightly builds, run with -Z macro-backtrace for more info)

For more information about this error, try `rustc --explain E0277`.
error: could not compile `pallet-multisig` (lib test) due to 1 previous error 
```




## For reviewers:

(If there is a better solution, please let me know!)

The first commit contains actual attempt to fix the problem:
3c5499e.
The second commit is just removal of `BlockHashCount` from all other
places where not needed by default.

Closes: #1657

---------

Co-authored-by: Bastian Köcher <[email protected]>

Author: bkontur

bridges/bin/runtime-common/src/mock.rs

@@ -148,7 +148,6 @@ impl frame_system::Config for TestRuntime {
 	type AccountId = ThisChainAccountId;
 	type Block = ThisChainBlock;
 	type AccountData = pallet_balances::AccountData<ThisChainBalance>;
-	type BlockHashCount = ConstU32<250>;
 }
 
 impl pallet_utility::Config for TestRuntime {

bridges/snowbridge/pallets/inbound-queue/src/mock.rs

@@ -43,10 +43,6 @@ frame_support::construct_runtime!(
 pub type Signature = MultiSignature;
 pub type AccountId = <<Signature as Verify>::Signer as IdentifyAccount>::AccountId;
 
-parameter_types! {
-	pub const BlockHashCount: u64 = 250;
-}
-
 type Balance = u128;
 
 #[derive_impl(frame_system::config_preludes::TestDefaultConfig)]
@@ -60,7 +56,6 @@ impl frame_system::Config for Test {
 	type AccountId = AccountId;
 	type Lookup = IdentityLookup<Self::AccountId>;
 	type RuntimeEvent = RuntimeEvent;
-	type BlockHashCount = BlockHashCount;
 	type PalletInfo = PalletInfo;
 	type AccountData = pallet_balances::AccountData<u128>;
 	type Nonce = u64;

bridges/snowbridge/pallets/outbound-queue/src/mock.rs

@@ -33,10 +33,6 @@ frame_support::construct_runtime!(
 	}
 );
 
-parameter_types! {
-	pub const BlockHashCount: u64 = 250;
-}
-
 #[derive_impl(frame_system::config_preludes::TestDefaultConfig)]
 impl frame_system::Config for Test {
 	type BaseCallFilter = Everything;
@@ -48,7 +44,6 @@ impl frame_system::Config for Test {
 	type AccountId = AccountId;
 	type Lookup = IdentityLookup<Self::AccountId>;
 	type RuntimeEvent = RuntimeEvent;
-	type BlockHashCount = BlockHashCount;
 	type PalletInfo = PalletInfo;
 	type Nonce = u64;
 	type Block = Block;

bridges/snowbridge/pallets/system/src/mock.rs

@@ -3,7 +3,7 @@
 use crate as snowbridge_system;
 use frame_support::{
 	derive_impl, parameter_types,
-	traits::{tokens::fungible::Mutate, ConstU128, ConstU64, ConstU8},
+	traits::{tokens::fungible::Mutate, ConstU128, ConstU8},
 	weights::IdentityFee,
 	PalletId,
 };
@@ -106,7 +106,6 @@ impl frame_system::Config for Test {
 	type AccountId = AccountId;
 	type Lookup = IdentityLookup<Self::AccountId>;
 	type RuntimeEvent = RuntimeEvent;
-	type BlockHashCount = ConstU64<250>;
 	type PalletInfo = PalletInfo;
 	type AccountData = pallet_balances::AccountData<u128>;
 	type Nonce = u64;

cumulus/pallets/collator-selection/src/mock.rs

@@ -46,7 +46,6 @@ frame_support::construct_runtime!(
 );
 
 parameter_types! {
-	pub const BlockHashCount: u64 = 250;
 	pub const SS58Prefix: u8 = 42;
 }
 
@@ -65,7 +64,6 @@ impl system::Config for Test {
 	type Lookup = IdentityLookup<Self::AccountId>;
 	type Block = Block;
 	type RuntimeEvent = RuntimeEvent;
-	type BlockHashCount = BlockHashCount;
 	type Version = ();
 	type PalletInfo = PalletInfo;
 	type AccountData = pallet_balances::AccountData<u64>;

cumulus/pallets/parachain-system/src/mock.rs

@@ -55,7 +55,6 @@ frame_support::construct_runtime!(
 );
 
 parameter_types! {
-	pub const BlockHashCount: u64 = 250;
 	pub Version: RuntimeVersion = RuntimeVersion {
 		spec_name: sp_version::create_runtime_str!("test"),
 		impl_name: sp_version::create_runtime_str!("system-test"),
@@ -74,7 +73,6 @@ parameter_types! {
 #[derive_impl(frame_system::config_preludes::TestDefaultConfig)]
 impl frame_system::Config for Test {
 	type Block = Block;
-	type BlockHashCount = BlockHashCount;
 	type Version = Version;
 	type OnSetCode = ParachainSetCode<Self>;
 }

cumulus/pallets/xcmp-queue/src/mock.rs

@@ -52,7 +52,6 @@ frame_support::construct_runtime!(
 );
 
 parameter_types! {
-	pub const BlockHashCount: u64 = 250;
 	pub const SS58Prefix: u8 = 42;
 }
 
@@ -73,7 +72,6 @@ impl frame_system::Config for Test {
 	type Lookup = IdentityLookup<Self::AccountId>;
 	type Block = Block;
 	type RuntimeEvent = RuntimeEvent;
-	type BlockHashCount = BlockHashCount;
 	type Version = ();
 	type PalletInfo = PalletInfo;
 	type AccountData = pallet_balances::AccountData<u64>;

cumulus/parachains/common/src/impls.rs

@@ -222,7 +222,6 @@ mod tests {
 	);
 
 	parameter_types! {
-		pub const BlockHashCount: u64 = 250;
 		pub BlockLength: limits::BlockLength = limits::BlockLength::max(2 * 1024);
 		pub const AvailableBlockRatio: Perbill = Perbill::one();
 		pub const MaxReserves: u32 = 50;
@@ -240,7 +239,6 @@ mod tests {
 		type Lookup = IdentityLookup<Self::AccountId>;
 		type Block = Block;
 		type RuntimeEvent = RuntimeEvent;
-		type BlockHashCount = BlockHashCount;
 		type BlockLength = BlockLength;
 		type BlockWeights = ();
 		type DbWeight = ();

cumulus/parachains/pallets/collective-content/src/mock.rs

@@ -18,9 +18,7 @@
 pub use crate as pallet_collective_content;
 use crate::WeightInfo;
 use frame_support::{
-	derive_impl, ord_parameter_types, parameter_types,
-	traits::{ConstU32, ConstU64},
-	weights::Weight,
+	derive_impl, ord_parameter_types, parameter_types, traits::ConstU32, weights::Weight,
 };
 use frame_system::EnsureSignedBy;
 use sp_runtime::{traits::IdentityLookup, BuildStorage};
@@ -70,7 +68,6 @@ impl frame_system::Config for Test {
 	type AccountId = AccountId;
 	type Lookup = IdentityLookup<Self::AccountId>;
 	type RuntimeEvent = RuntimeEvent;
-	type BlockHashCount = ConstU64<250>;
 	type Version = ();
 	type PalletInfo = PalletInfo;
 	type AccountData = ();

polkadot/runtime/common/src/assigned_slots/mod.rs

@@ -671,10 +671,6 @@ mod tests {
 		type OverarchingCall = RuntimeCall;
 	}
 
-	parameter_types! {
-		pub const BlockHashCount: u32 = 250;
-	}
-
 	#[derive_impl(frame_system::config_preludes::TestDefaultConfig)]
 	impl frame_system::Config for Test {
 		type BaseCallFilter = frame_support::traits::Everything;
@@ -689,7 +685,6 @@ mod tests {
 		type Lookup = IdentityLookup<Self::AccountId>;
 		type Block = Block;
 		type RuntimeEvent = RuntimeEvent;
-		type BlockHashCount = BlockHashCount;
 		type DbWeight = ();
 		type Version = ();
 		type PalletInfo = PalletInfo;