Moves all test runtimes to use derive_impl (#2409)

Step in https://github.com/paritytech/polkadot-sdk/issues/171

This PR adds `derive_impl` on all `frame_system` config impls for mock
runtimes. The overridden configs are maintained as of now to ensure
minimal changes.

---------

Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

cumulus/parachains/runtimes/starters/shell/src/lib.rs

@@ -52,7 +52,7 @@ use sp_version::RuntimeVersion;
 
 // A few exports that help ease life for downstream crates.
 pub use frame_support::{
-	construct_runtime,
+	construct_runtime, derive_impl,
 	dispatch::DispatchClass,
 	genesis_builder_helper::{build_config, create_default_config},
 	parameter_types,
@@ -143,6 +143,7 @@ parameter_types! {
 	pub const SS58Prefix: u8 = 42;
 }
 
+#[derive_impl(frame_system::config_preludes::TestDefaultConfig as frame_system::DefaultConfig)]
 impl frame_system::Config for Runtime {
 	/// The identifier used to distinguish between accounts.
 	type AccountId = AccountId;