Play a sound when a call is disconnecting/reconnecting

### Your use case

#### What would you like to do?

I would like it so that if you're in a call and there's a connection issue it plays some kind of tone to let you know that this a connection issue.

#### Why would you like to do it?
Right now, you have to look at the phone to see there is a connection issue. This is often fine but if you're on a call with someone where they may mute themselves for a bit or are just in a very quiet environment it becomes a problem. Because then you are talking and unless you look at the phone you won't know that the call is having a connection problem.

#### How would you like to achieve it?
I don't know how exactly but facebook messenger handles this nicely with a gentle tone with the call was connected but is now having connection issues.

### Have you considered any alternatives?

of course I can look at the phone, but that's not always easy to do, especially for long calls and when it's cold.

### Additional context

A bit related to https://github.com/vector-im/element-android/issues/2447 because I think I'm most often felt the pain here when walking around and my phone connects/disconnects from wifi.

### Are you willing to provide a PR?

No