Remove sudo support from prepare_test_env
    
    This is broken since only some of the commands requiring root
    access were prefixed with $SUDO. Removing instead of repairing it
    since we do not have a use case for the functionality anyways -
    the containers executing Salt related commands need to run as root,
    and the linting containers using less privileged users do not call
    this script.
    
    Signed-off-by: Georg Pfuetzenreuter <mail@georg-pfuetzenreuter.net>