scan only *.gid files in /etc/sfa/trusted_roots previous behaviour was to scan all files, which was error-prone
scan only *.gid files in /etc/sfa/trusted_roots
previous behaviour was to scan all files, which was error-prone

onelab-eu/sfa,yippeecw/sfa,onelab-eu/sfa,onelab-eu/sfa,yippeecw/sfa,yippeecw/sfa