install: Add a friendly message
install: Add a friendly message

The initial search for remotes and refs can take a while.
Provide a message similar to what we say for updates.

Closes: #2371
Approved by: alexlarsson

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