Avoid accidentally reusing a gid in tests
Avoid accidentally reusing a gid in tests

Some platforms have groups in odd ranges, make sure the gid we select is
not in use.

Signed-off-by: Bryan McLellan <9da9e2973b9c72b95f1bc7169993146760fceeb1@loftninjas.org>

higanworks/chef,mattray/chef,Tensibai/chef,mattray/chef,mwrock/chef,higanworks/chef,mattray/chef,mwrock/chef,jaymzh/chef,gene1wood/chef,gene1wood/chef,chef/chef,nvwls/chef,Tensibai/chef,MsysTechnologiesllc/chef,MsysTechnologiesllc/chef,nvwls/chef,gene1wood/chef,chef/chef,Tensibai/chef,MsysTechnologiesllc/chef,higanworks/chef,tas50/chef-1,jaymzh/chef,mwrock/chef,tas50/chef-1,mattray/chef,Tensibai/chef,jaymzh/chef,nvwls/chef,jaymzh/chef,chef/chef,chef/chef,MsysTechnologiesllc/chef,gene1wood/chef,nvwls/chef,higanworks/chef,mwrock/chef,higanworks/chef,nvwls/chef,nvwls/chef,mattray/chef,Tensibai/chef,tas50/chef-1,tas50/chef-1