Fix build: use Default::default() for FxHashMap type alias

TransientStorage is a type alias for FxHashMap which uses FxBuildHasher,
so HashMap::new() (which requires RandomState) doesn't compile. Use
default() which works with any hasher.

Author: ilitteri

crates/vm/levm/src/vm.rs

@@ -95,7 +95,7 @@ impl Substate {
             accessed_storage_slots,
             created_accounts: FxHashSet::default(),
             refunded_gas: 0,
-            transient_storage: TransientStorage::new(),
+            transient_storage: TransientStorage::default(),
             logs: Vec::new(),
         }
     }