Upgrade: add gidnumber to trusted domain entry
    
    The trusted domain entries created in earlier versions are missing gidnumber.
    During upgrade, a new plugin will read the gidnumber of the fallback group
    cn=Default SMB Group and add this value to trusted domain entries which do
    not have a gidNumber.
    
    https://pagure.io/freeipa/issue/6827
    
    Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>