Search for `name` in labels name and returns corresponding tag string.
        Tag name is label name if not specified.
        Returns None if name was not found.

def _label_to_tag(self, name, labels, scraper_config, tag_name=None):
        """
        Search for `name` in labels name and returns corresponding tag string.
        Tag name is label name if not specified.
        Returns None if name was not found.
        """
        value = labels.get(name)
        if value:
            return self._format_tag(tag_name or name, value, scraper_config)
        else:
            return None