Disable exit button after checking update trigger button.

worker.cpp

@@ -290,6 +290,8 @@ void Worker::privateUpdate() {
         // update procedure, even if ISMAS-trigger is not correctly set ("WAIT")
     }
 
+    emit this->disableExit();
+
     QDir customerRepository(m_customerRepository);
     QDir customerRepositoryEtc(QDir::cleanPath(m_customerRepository + QDir::separator() + "etc/"));