Helper storage item to store the total balance that should be kept on Relay Chain after
it is consumed from the RcMigratedBalance storage item and sent to the Asset Hub.
This let us to take the value from the RcMigratedBalance storage item and keep the
SignalMigrationFinish stage to be idempotent while preserving these values for tests and
later discoveries.
Helper storage item to store the total balance that should be kept on Relay Chain after it is consumed from the
RcMigratedBalancestorage item and sent to the Asset Hub.This let us to take the value from the
RcMigratedBalancestorage item and keep theSignalMigrationFinishstage to be idempotent while preserving these values for tests and later discoveries.