Dear Maintainer,

gnome-package-updater cannot find package upgrades, until after running 'apt
update'.

Steps:
0. Make sure that there are packages to upgrade without running 'apt update'
because that breaks the steps
1. Run gnome-package-updater
2. It does not find any package upgrades
3. Close gnome-package-updater
4. Run in a terminal 'sudo apt update'
5. apt will show the number of packages to upgrade
6. Run gnome-package-updater
7. It will show the package upgrades

What should happen:
gnome-package-updater finds package upgrades, when they are available, without
having to run 'apt update'.

Best,
Amr