Releasing 2.0.0-alpha.4 (#5279)

* Version bump

* Split generate_changelog.sh into separate script

Can be run in the format `generate_changelog.sh $previous_version $version`.

* remove early exit from publish_draft_release.sh

* adding changelog

* ci: change last_github_release to also find pre-releases

Co-authored-by: Martin Pugh <[email protected]>

Author: valeriikharkin

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pallet-evm"
-version = "2.0.0-alpha.3"
+version = "2.0.0-alpha.4"
 authors = ["Parity Technologies <[email protected]>"]
 edition = "2018"
 license = "GPL-3.0"
@@ -11,14 +11,14 @@ description = "FRAME EVM contracts pallet"
 [dependencies]
 serde = { version = "1.0.101", optional = true, features = ["derive"] }
 codec = { package = "parity-scale-codec", version = "1.2.0", default-features = false }
-frame-support = { version = "2.0.0-alpha.2", default-features = false, path = "../support" }
-frame-system = { version = "2.0.0-alpha.2", default-features = false, path = "../system" }
-pallet-timestamp = { version = "2.0.0-alpha.2", default-features = false, path = "../timestamp" }
-pallet-balances = { version = "2.0.0-alpha.2", default-features = false, path = "../balances" }
-sp-core = { version = "2.0.0-alpha.2", default-features = false, path = "../../primitives/core" }
-sp-runtime = { version = "2.0.0-alpha.2", default-features = false, path = "../../primitives/runtime" }
-sp-std = { version = "2.0.0-alpha.2", default-features = false, path = "../../primitives/std" }
-sp-io = { version = "2.0.0-alpha.2", default-features = false, path = "../../primitives/io" }
+frame-support = { version = "2.0.0-alpha.4", default-features = false, path = "../support" }
+frame-system = { version = "2.0.0-alpha.4", default-features = false, path = "../system" }
+pallet-timestamp = { version = "2.0.0-alpha.4", default-features = false, path = "../timestamp" }
+pallet-balances = { version = "2.0.0-alpha.4", default-features = false, path = "../balances" }
+sp-core = { version = "2.0.0-alpha.4", default-features = false, path = "../../primitives/core" }
+sp-runtime = { version = "2.0.0-alpha.4", default-features = false, path = "../../primitives/runtime" }
+sp-std = { version = "2.0.0-alpha.4", default-features = false, path = "../../primitives/std" }
+sp-io = { version = "2.0.0-alpha.4", default-features = false, path = "../../primitives/io" }
 primitive-types = { version = "0.6.2", default-features = false, features = ["rlp"] }
 rlp = { version = "0.4", default-features = false }
 evm = { version = "0.15", default-features = false }