Remove nested eventloop crash when clicking on notification

Nested eventloops are evil, they can lead to the notification being deleted while its code is still running.

Just remove the dialog to fix it - if I click on the notification I want to go to the room and not have to interact with another dialog. I.e. in my POV, this also improves the usability of ruqola.

Application: Ruqola (ruqola), signal: Segmentation fault
Content of s_kcrashErrorMessage: (null)
[KCrash Handler]
#5  0x00007f6fd3e0e170 in QObjectPrivate::maybeSignalConnected(unsigned int) const () at /usr/lib/libQt5Core.so.5
#6  0x00007f6fd3e1b5d5 in  () at /usr/lib/libQt5Core.so.5
#7  0x00007f6fd6fb4901 in KNotification::activated(unsigned int) (this=0x5578bc13d060, _t1=0) at src/KF5Notifications_autogen/EWIEGA46WW/moc_knotification.cpp:271
#8  0x00007f6fd6fbadbd in KNotification::activate(unsigned int) (this=0x5578bc13d060, action=0) at /home/milian/projects/kf5/src/frameworks/knotifications/src/knotification.cpp:330
#9  0x00007f6fd6fbf4a7 in KNotificationManager::notificationActivated(int, int) (this=0x7f6fd70216b0 <(anonymous namespace)::Q_QGS_s_self::innerFunction()::holder>, id=9, action=0) at /home/milian/projects/kf5/src/frameworks/knotifications/src/knotificationmanager.cpp:243
#10 0x00007f6fd6fc3fac in QtPrivate::FunctorCall<QtPrivate::IndexesList<0, 1>, QtPrivate::List<int, int>, void, void (KNotificationManager::*)(int, int)>::call(void (KNotificationManager::*)(int, int), KNotificationManager*, void**) (f=(void (KNotificationManager::*)(KNotificationManager * const, int, int)) 0x7f6fd6fbf38e <KNotificationManager::notificationActivated(int, int)>, o=0x7f6fd70216b0 <(anonymous namespace)::Q_QGS_s_self::innerFunction()::holder>, arg=0x7ffecc2c8260) at /usr/include/qt/QtCore/qobjectdefs_impl.h:152
#11 0x00007f6fd6fc3bac in QtPrivate::FunctionPointer<void (KNotificationManager::*)(int, int)>::call<QtPrivate::List<int, int>, void>(void (KNotificationManager::*)(int, int), KNotificationManager*, void**) (f=(void (KNotificationManager::*)(KNotificationManager * const, int, int)) 0x7f6fd6fbf38e <KNotificationManager::notificationActivated(int, int)>, o=0x7f6fd70216b0 <(anonymous namespace)::Q_QGS_s_self::innerFunction()::holder>, arg=0x7ffecc2c8260) at /usr/include/qt/QtCore/qobjectdefs_impl.h:185
#12 0x00007f6fd6fc3490 in QtPrivate::QSlotObject<void (KNotificationManager::*)(int, int), QtPrivate::List<int, int>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (which=1, this_=0x5578ba921da0, r=0x7f6fd70216b0 <(anonymous namespace)::Q_QGS_s_self::innerFunction()::holder>, a=0x7ffecc2c8260, ret=0x0) at /usr/include/qt/QtCore/qobjectdefs_impl.h:418
#13 0x00007f6fd3e1ba26 in  () at /usr/lib/libQt5Core.so.5
#14 0x00007f6fd6fb4f68 in KNotificationPlugin::actionInvoked(int, int) (this=0x5578ba9233c0, _t1=9, _t2=0) at src/KF5Notifications_autogen/EWIEGA46WW/moc_knotificationplugin.cpp:155
#15 0x00007f6fd6fdf7ed in NotifyByPopup::onNotificationActionInvoked(unsigned int, QString const&) (this=0x5578ba9233c0, notificationId=108, actionKey=...) at /home/milian/projects/kf5/src/frameworks/knotifications/src/notifybypopup.cpp:219