Ensure shard is primary shard for db on DDL operation legacy paths

Similarly to what we do in the new DDL coordinators, or even the legacy shard collection, we should ensure that the current shard is the primary shard for the DB. This is now necessary on the legacy DDL paths because they run on the shard. Otherwise, a request from a stale mongos could potentially execute on a non-primary shard.
This needs to be addressed for the legacy dropCollection and dropDatabase