OK, this is annoying. GNOME Software intentionally does *not*
clear the 'download' or 'reboot and update' button when you hit
the refresh button, it just leaves them sitting there while the
refresh happens. So let's specifically require the 'refreshing'
text to appear and go away before we try and click on download
or apply.
Signed-off-by: Adam Williamson <awilliam@redhat.com>