gnome-software: A string change

[Milan Crha <mcrha redhat com>]

        Hello,
just a quick notice, a translatable string had been changed in the
gnome-software sources few minutes ago, as had been agreed on at:
https://gitlab.gnome.org/GNOME/gnome-software/-/issues/1574

It changes:

   No updates have been installed on this system.

into:

   No Updates Installed


No other changes made.
        Bye,
        Milan