[pallet_xcm] Forgotten migration to XCMv4 + added try-state to the pallet_xcm (#3228)

Relates to: https://github.com/paritytech/polkadot-sdk/issues/3214

## TODO

- [ ] backport to the `1.7.0` release

cumulus/parachains/runtimes/contracts/contracts-rococo/src/lib.rs

@@ -103,6 +103,8 @@ pub type Migrations = (
 	pallet_contracts::Migration<Runtime>,
 	// unreleased
 	cumulus_pallet_xcmp_queue::migration::v4::MigrationToV4<Runtime>,
+	// permanent
+	pallet_xcm::migration::MigrateToLatestXcmVersion<Runtime>,
 );
 
 type EventRecord = frame_system::EventRecord<