Fixes #6682: Move the katello-debug.sh script instead of linking it

I have not been able to test this.. but I think it should work :)
To keep consistency, why not something similar to this:

    install -d -m0755 %{buildroot}/usr/share/foreman/script/foreman-debug.d/
    install -m 755 script/katello-debug.sh %{buildroot}/usr/share/foreman/script/foreman-debug.d/katello-debug.sh

It also leaves the script in ${homedir}/script, but that's what's done elsewhere as well (e.g. the cron job)