add unstable support for MSC4125

from https://gitlab.com/famedly/conduit/-/merge_requests/626 with code fixes and clippy lint fixes

MSC4125: https://github.com/matrix-org/matrix-spec-proposals/pull/4125

Co-authored-by: Matthias Ahouansou <matthias@ahouansou.cz>
Signed-off-by: strawberry <strawberry@puppygock.gay>

src/service/rooms/state/mod.rs

@@ -68,11 +68,15 @@ impl Service {
 						continue;
 					};
 
-					services()
-						.rooms
-						.state_cache
-						.update_membership(room_id, &user_id, membership_event, &pdu.sender, None, false)
-						.await?;
+					services().rooms.state_cache.update_membership(
+						room_id,
+						&user_id,
+						membership_event,
+						&pdu.sender,
+						None,
+						None,
+						false,
+					)?;
 				},
 				TimelineEventType::SpaceChild => {
 					services()