Deletes a tag of a repository with given name.

        :param project_id: The ID of a project
        :param tag_name: The name of a tag
        :return: Dictionary containing delete tag
        :raise: HttpError: If invalid response returned

def delete_repository_tag(self, project_id, tag_name):
        """
        Deletes a tag of a repository with given name.

        :param project_id: The ID of a project
        :param tag_name: The name of a tag
        :return: Dictionary containing delete tag
        :raise: HttpError: If invalid response returned
        """
        return self.delete('/projects/{project_id}/repository/tags/{tag_name}'.format(
            project_id=project_id, tag_name=tag_name))