Handle the delay before showing a newly created room on "Explore rooms" screen

### Your use case

#### What would you like to do?
I'm a member of a public space with some rooms in it. When I create a new private room within that space, I get redirected back to the Explore rooms screen.
There's a small delay between me creating a new room and the room actually showing up on that screen. Sometimes, I can even see the room change its name from Empty room to whatever I named it.
If the space had a lot of rooms or I had a slow connection, this delay could increase. That would probably make me think that the room creation didn't happen and I'd try to create it again.

For example, I've just created a new room called "What?" and got back to this screen:

After a second or two, I can see the room:

#### Why would you like to do it?
To make the app seem more reliable.
#### How would you like to achieve it?
I guess we could add a spinner on the Explore rooms screen and wait for the room to be fully created.

### Have you considered any alternatives?

Alternatively, we could make the user wait for the room to be fully created before we redirect them to the Explore rooms screen.

### Additional context

The easiest way to reproduce this behaviour is to have a poor connection or a lot of rooms within a space.

### Are you willing to provide a PR?

No