Fix memory leak

Code looks valid, but valgrind is reporting a leak here. In any
case Qt docs suggest not to use addAction and parent the
actions to the QActionGroup instead, so let's do that (and
it solves the reported leak)

src/app/qgisapp.cpp

@@ -2419,10 +2419,9 @@ void QgisApp::refreshProfileMenu()
   Q_FOREACH ( const QString &name, userProfileManager()->allProfiles() )
   {
     std::unique_ptr< QgsUserProfile > namedProfile( userProfileManager()->profileForName( name ) );
-    QAction *action = new QAction( namedProfile->icon(), namedProfile->alias(), mConfigMenu );
+    QAction *action = new QAction( namedProfile->icon(), namedProfile->alias(), profileGroup );
     action->setToolTip( namedProfile->folder() );
     action->setCheckable( true );
-    profileGroup->addAction( action );
     mConfigMenu->addAction( action );
 
     if ( name == activeName )