startstop: test fmw on Workstation and KDE
    
    When we added fmw to apps_startstop tests it was only preinstalled
    on Silverblue, but now it's on KDE and Workstation too.
    
    Also includes a needle that matches on part of the UI, which
    will work on all desktops.
    
    Signed-off-by: Adam Williamson <awilliam@redhat.com>