run: Allow selecting an installation
run: Allow selecting an installation

It may be an unlikely case, but if the same app
is installed in multiple installations, there was
no way to select which one to run, so far.

Closes: #2146

Closes: #2158
Approved by: alexlarsson

flatpak/flatpak,flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak,flatpak/flatpak