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/salary/src/tests.rs

@@ -20,7 +20,7 @@
 use std::collections::BTreeMap;
 
 use frame_support::{
-	assert_noop, assert_ok,
+	assert_noop, assert_ok, derive_impl,
 	pallet_prelude::Weight,
 	parameter_types,
 	traits::{tokens::ConvertRank, ConstU32, ConstU64, Everything},
@@ -49,6 +49,8 @@ parameter_types! {
 	pub BlockWeights: frame_system::limits::BlockWeights =
 		frame_system::limits::BlockWeights::simple_max(Weight::from_parts(1_000_000, 0));
 }
+
+#[derive_impl(frame_system::config_preludes::TestDefaultConfig as frame_system::DefaultConfig)]
 impl frame_system::Config for Test {
 	type BaseCallFilter = Everything;
 	type BlockWeights = ();