Fix a bug in prepare_grouped_command_lines (gzip.c) for files without suffix
Fix a bug in prepare_grouped_command_lines (gzip.c) for files without suffix

mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs