android: disable ConnectionService for the Jitsi Meet app

It's the source of uncountable problems for which we don't have a good
solution, since they are caused by buggy implementations of self-managed
connection services by manufacturers.

android/app/src/main/java/org/jitsi/meet/MainActivity.java

 /*
- * Copyright @ 2018-present 8x8, Inc.
- * Copyright @ 2017-2018 Atlassian Pty Ltd
+ * Copyright @ 2017-present 8x8, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
             = new JitsiMeetConferenceOptions.Builder()
                 .setWelcomePageEnabled(true)
                 .setServerURL(buildURL("https://meet.jit.si"))
+                .setFeatureFlag("call-integration.enabled", false)
                 .build();
         JitsiMeet.setDefaultConferenceOptions(defaultOptions);