🐛 Filter destination rooms in admin API

No filtering existed on the rooms that were returned. We were returning
all rooms, but still showing the counter as accurate.

synapse/storage/databases/main/transactions.py

@@ -600,6 +600,7 @@ def get_destination_rooms_paginate_txn(
                     start=start,
                     limit=limit,
                     retcols=("room_id", "stream_ordering"),
+                    keyvalues={"destination": destination},
                     order_direction=order,
                 ),
             )