Fix crash when deleting activity from activity manager
When deleting activity from activity manager, the delete button is destroyed while handling onClicked signal. This happens because ActivitySettings.deleteActivity() is calling QMessageBox::question() that waits for user confirmation.
Change deleteActivity call to use QMetaObject with QueuedConnection as the connectivity type. This allows the delete button to be destroyed without having to wait for user confirmation.
Edited by Willyanto Willyanto