prevent NPE if UI has already been teared down

Resolves #2321

Signed-off-by: Andy Scherzinger <info@andy-scherzinger.de>

app/src/main/java/com/nextcloud/talk/controllers/ChatController.kt

@@ -355,9 +355,8 @@ class ChatController(args: Bundle) :
                                 conversationUser
                             )
 
-                        setupSwipeToReply()
-
                         try {
+                            setupSwipeToReply()
                             setupMentionAutocomplete()
                             checkShowCallButtons()
                             checkShowMessageInputView()