def _remove_trailing_hr_tag(*, markdown: str) -> str:
    """
    Remove a trailing `<hr>` tag from a specified markdown string.

    Parameters
    ----------
    markdown : str
        Target markdown string.

    Returns
    -------
    markdown : str
        Result markdown string.
    """
    markdown = markdown.strip()
    hr_tag: str = '<hr>'
    if markdown.endswith(hr_tag):
        markdown = markdown[:-len(hr_tag)]
    markdown = markdown.strip()
    return markdown