Active session after call is hung-up with callkit on second call

## Steps to reproduce
1. Start a call with talk-ios (to talk-web)
2. Minimize talk-ios
3. Get a second (phone) call on the phone
4. Select "End & Accept"

### Expected behaviour
The talk call is ended and the active session as well

### Actual behaviour
The talk call is ended, but the session in the room is still active.

I don't think this explains #595, but stumbled accross this while having a look. Also the active session is terminated after a few minutes, so I don't think this one is too serious, but the callflag is resetted immediatly, so I guess the session should be as well.

## Device information

**Device:** iPhone 11 Pro

**iOS version:** 15.0

**Talk version:** 12.2.0

## Server information

**Nextcloud version:** 22.1.1

**Talk version:** 12.1.2

**Custom Signaling server configured:** yes

**Custom TURN server configured:** yes

**Custom STUN server configured:** yes