Implement Contains for pallet-membership (#6518)

* implement Contains for pallet-membership

* bump version

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

@@ -98,7 +98,7 @@ pub const VERSION: RuntimeVersion = RuntimeVersion {
 	// implementation changes and behavior does not, then leave spec_version as
 	// is and increment impl_version.
 	spec_version: 254,
-	impl_version: 0,
+	impl_version: 1,
 	apis: RUNTIME_API_VERSIONS,
 	transaction_version: 1,
 };