Keep the room creation spinner open until the new room is received from server (#31311)

In the upcoming work for encrypted state, we need to keep the spinner
until the m.room.encryption event is received. This change keeps the
spinner just a little longer than before: until the room is received
from the server.

I'm submitting this change partly because I think it makes sense to
delay until we can confirm the room exists and partly to separate this
change from other changes that will be involved in encrypted state. That
way if this causes problems we can discuss or revert it separately.

src/createRoom.ts

@@ -316,9 +316,6 @@ export default async function createRoom(client: MatrixClient, opts: IOpts): Pro
                 return Promise.reject(err);
             }
         })
-        .finally(function () {
-            if (modal) modal.close();
-        })
         .then(async (res): Promise<void> => {
             roomId = res.room_id;
 
@@ -340,6 +337,9 @@ export default async function createRoom(client: MatrixClient, opts: IOpts): Pro
 
             if (opts.dmUserId) await Rooms.setDMRoom(client, roomId, opts.dmUserId);
         })
+        .finally(function () {
+            if (modal) modal.close();
+        })
         .then(() => {
             if (opts.parentSpace) {
                 return SpaceStore.instance.addRoomToSpace(