* feat(default-flatpaks): Support for notifications that inform the user before flatpak install/uninstall procedure begins
This can be implemented to be more readable maybe, but this should work.
* chore(default-flatpaks): There is no need to call notifications true statement twice
* chore(default-flatpaks): Make starting notifications consistent with finished ones
* chore(default-flatpaks): Use "listed" term rather than "some"
* chore(default-flatpaks): Use "some" notification only for uninstalling flatpaks
