Add WakeLock to dismiss ringing call screen when call is cancelled (#4478)

* Add `WakeLock` to dismiss ringing call screen when call is cancelled

We had already some checks in place to automatically cancel a ringing call notification/screen when the call was no longer active, but the `RoomInfo` updates weren't being processed because the app was 'paused'.

The partial wakelock should ensure these room info updates are handled.

* Add mutual exclusion to `ActiveCallManager` methods to improve thread safety

features/call/test/src/main/kotlin/io/element/android/features/call/test/FakeElementCallEntryPoint.kt

@@ -30,7 +30,7 @@ class FakeElementCallEntryPoint(
         startCallResult(callType)
     }
 
-    override fun handleIncomingCall(
+    override suspend fun handleIncomingCall(
         callType: CallType.RoomCall,
         eventId: EventId,
         senderId: UserId,