Rename pallet trait Trait to Config (#7599)

* rename Trait to Config

* add test asserting using Trait is still valid.

* fix ui tests

substrate/primitives/runtime/src/offchain/storage_lock.rs

@@ -438,11 +438,11 @@ pub trait BlockNumberProvider {
 	///
 	/// In case of using crate `sp_runtime` without the crate `frame`
 	/// system, it is already implemented for
-	/// `frame_system::Module<T: Trait>` as:
+	/// `frame_system::Module<T: Config>` as:
 	///
 	/// ```ignore
 	/// fn current_block_number() -> Self {
-	///     frame_system::Module<Trait>::block_number()
+	///     frame_system::Module<Config>::block_number()
 	/// }
 	/// ```
 	/// .