Use the commit date in UTC as folder name

def snapshot_folder():
    """
    Use the commit date in UTC as folder name
    """
    logger.info("Snapshot folder")
    try:
        stdout = subprocess.check_output(["git", "show", "-s", "--format=%cI", "HEAD"])
    except subprocess.CalledProcessError as e:
        logger.error("Error: {}".format(e.output.decode('ascii', 'ignore').strip()))
        sys.exit(2)
    except FileNotFoundError as e:
        logger.error("Error: {}".format(e))
        sys.exit(2)
    ds = stdout.decode('ascii', 'ignore').strip()
    dt = datetime.fromisoformat(ds)
    utc = dt - dt.utcoffset()
    return utc.strftime("%Y%m%d_%H%M%S")