Bump a couple of disk sizes (KDE package set, Workstation boot)
    
    Some tests on Rawhide started failing back in April due to
    insufficient space. I dug into it for an hour or two but can't
    find any big smoking guns where unnecessary packages got added
    to groups or some package suddenly got bigger or anything, so I
    can't find any real bugs to report here; we're just gonna have
    to bump the sizes.
    
    Signed-off-by: Adam Williamson <awilliam@redhat.com>