Don't redisplay notifications after they have been dismissed

Fixes #5751
Fixes #6218
// FREEBIE

src/org/thoughtcrime/securesms/jobs/PushDecryptJob.java

@@ -111,7 +111,6 @@ public class PushDecryptJob extends ContextJob {
 
     if (!IdentityKeyUtil.hasIdentityKey(context)) {
       Log.w(TAG, "Skipping job, waiting for migration...");
-      MessageNotifier.updateNotification(context, null, true, -2);
       return;
     }