Identify the language correctly for older versions

[AA-Turner]

Closes #241

See

https://docs.python.org/3.10/_static/documentation_options.js

var DOCUMENTATION_OPTIONS = {
    URL_ROOT: document.getElementById("documentation_options").getAttribute('data-url_root'),
    VERSION: '3.10.16',
    LANGUAGE: 'None',
    COLLAPSE_INDEX: false,
    BUILDER: 'html',
    FILE_SUFFIX: '.html',
    LINK_SUFFIX: '.html',
    HAS_SOURCE: true,
    SOURCELINK_SUFFIX: '.txt',
    NAVIGATION_WITH_KEYS: false
};

vs

https://docs.python.org/3.11/_static/documentation_options.js

const DOCUMENTATION_OPTIONS = {
    VERSION: '3.11.11',
    LANGUAGE: 'en',
    COLLAPSE_INDEX: false,
    BUILDER: 'html',
    FILE_SUFFIX: '.html',
    LINK_SUFFIX: '.html',
    HAS_SOURCE: true,
    SOURCELINK_SUFFIX: '.txt',
    NAVIGATION_WITH_KEYS: false,
    SHOW_SEARCH_SUMMARY: true,
    ENABLE_SEARCH_SHORTCUTS: true,
};

A