File cleanup dont happen when Shard Rebalance is cancelled

As part of file-based rebalance, if a cancel rebalance is triggered by the user, as the first step RPC server is closed and the token cleanup (transferred data cleanup) is picked later on.

Even for local node's data cleanup, the DoCleanup() internally makes a call to the RPC Server, since it has been closed before the cleanup is triggered, the cleanup of files inside staging2 directory don't happen. Till the start of the next rebalance these files will be present inside the staging2 folder