Bump collator version to 5.4 (#1131)

cumulus/Cargo.lock

@@ -7399,7 +7399,7 @@ dependencies = [
 
 [[package]]
 name = "polkadot-collator"
-version = "5.3.0"
+version = "5.4.0"
 dependencies = [
  "assert_cmd",
  "async-trait",

cumulus/polkadot-parachains/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "polkadot-collator"
-version = "5.3.0"
+version = "5.4.0"
 authors = ["Parity Technologies <admin@parity.io>"]
 build = "build.rs"
 edition = "2021"