[Cloud SIG] Use util-linux instead of util-linux-ng
    
    Although util-linux rpm in CentOS8 Provides util-linux-ng but it
    fails with:
    No match for group package "util-linux-ng".
    
    Some package like SecretStorage fails to build due to missing util-linux
    with:-
    /usr/bin/xvfb-run: line 105: getopt: command not found
    
    Changing buildroot default for CloudSIG to rely on util-linux
    instead of util-linux-ng.