bugz.fedoraproject.org: replace %20 with + to fix redirect
    
    The backslash-escaped space in 'Fedora EPEL' was replaced with %20 in
    6e982da0d4 (bugz.fedoraproject.org: urlescape redirect instead of \,
    2023-03-15).  Unfortunately, mod_rewrite treats the %2 as a
    backreference, resulting in the string being 'Fedora0EPEL' which yeilds
    no results for EPEL bugs.
    
    We could possibly use on of the many RewriteRule flags to adjust the
    handling of backreferences, but using a `+` seems like the simpler
    option and works just as well in testing.
    
    Signed-off-by: Todd Zullinger <tmz@pobox.com>