Do not include rooms with an unknown room version in a sync response. (#10644)

A user will still see this room if it is in a local cache, but it will
not reappear if clearing the cache and reloading.

synapse/storage/roommember.py

@@ -30,6 +30,7 @@ class RoomsForUser:
     membership: str
     event_id: str
     stream_ordering: int
+    room_version_id: str
 
 
 @attr.s(slots=True, frozen=True, weakref_slot=False, auto_attribs=True)