'Driver for Target Tags. Calls helpers as needed.
return: (bool, [list of AuditIssues])'

def inspect_target_tags(self, item):

    errors = []
    target_tags = item.config.get('TargetTags', None)
    err = self._target_tags_valid(target_tags)
    (errors.extend(err) if err else None)
    if errors:
        return (False, errors)
    return (True, None)
