AppChooserDialog: Reload model when Sycoca database changes
Ensures that when you go looking for an app and it's not there, it shows up when you install it.
- Open with of a text file, had “kwrite” as default, uninstalled it, now had “kate” as default
- Installed kwrite, “kwrite” was shown as the new default
- Clicked “show all apps”, searched for “okteta”, it wasn’t there, installed it, it showed up
Should be good for 6.0