Wrap `get_local_public_room_list` call in `maybeDeferred` because it is cached and so does not always return a `Deferred`. `await` does not silently pass-through non-Deferreds like `yield` used to.
Wrap `get_local_public_room_list` call in `maybeDeferred` because it
is cached and so does not always return a `Deferred`.
`await` does not silently pass-through non-Deferreds like `yield` used to.

Signed-off-by: Olivier Wilkinson (reivilibre) <77cccf0d7a72ee0036f6f1a239d5c47ee8799014@librepush.net>

matrix-org/synapse,matrix-org/synapse,matrix-org/synapse,matrix-org/synapse,matrix-org/synapse,matrix-org/synapse