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>

substrate/frame/contracts/src/tests.rs

@@ -42,6 +42,7 @@ use assert_matches::assert_matches;
 use codec::Encode;
 use frame_support::{
 	assert_err, assert_err_ignore_postinfo, assert_err_with_weight, assert_noop, assert_ok,
+	derive_impl,
 	dispatch::{DispatchErrorWithPostInfo, PostDispatchInfo},
 	parameter_types,
 	storage::child,
@@ -332,6 +333,8 @@ parameter_types! {
 		);
 	pub static ExistentialDeposit: u64 = 1;
 }
+
+#[derive_impl(frame_system::config_preludes::TestDefaultConfig as frame_system::DefaultConfig)]
 impl frame_system::Config for Test {
 	type BaseCallFilter = frame_support::traits::Everything;
 	type BlockWeights = BlockWeights;