Fix PiP crash with IllegalStateException. Activity must be resumed to enter PiP mode.

https://sentry.tools.element.io/organizations/element/issues/1449388/events/2eb06349f6224481960a64916d51ae60/?project=59

features/call/impl/src/main/kotlin/io/element/android/features/call/impl/ui/ElementCallActivity.kt

@@ -281,7 +281,11 @@ class ElementCallActivity :
 
     @RequiresApi(Build.VERSION_CODES.O)
     override fun enterPipMode(): Boolean {
-        return enterPictureInPictureMode(getPictureInPictureParams())
+        return if (lifecycle.currentState.isAtLeast(Lifecycle.State.RESUMED)) {
+            enterPictureInPictureMode(getPictureInPictureParams())
+        } else {
+            false
+        }
     }
 
     @RequiresApi(Build.VERSION_CODES.O)