contracts: Convert to framev2 macros (#8157)

* contracts: Convert to framev2

* Reduce the API surface of the crate

* Remove unused import

* Merge import block

* Use pallet::metadata to reduce metadata diff

* Remove the explicit "Null" from AccountCounter

substrate/bin/node/executor/tests/basic.rs

@@ -17,7 +17,6 @@
 
 use codec::{Encode, Decode, Joiner};
 use frame_support::{
-	StorageMap,
 	traits::Currency,
 	weights::{GetDispatchInfo, DispatchInfo, DispatchClass},
 };

substrate/bin/node/runtime/src/lib.rs

@@ -71,7 +71,7 @@ pub use pallet_transaction_payment::{Multiplier, TargetedFeeAdjustment, Currency
 use pallet_session::{historical as pallet_session_historical};
 use sp_inherents::{InherentData, CheckInherentsResult};
 use static_assertions::const_assert;
-use pallet_contracts::WeightInfo;
+use pallet_contracts::weights::WeightInfo;
 
 #[cfg(any(feature = "std", test))]
 pub use sp_runtime::BuildStorage;