Enable creation date in the footer

There is a way to display the page creation date in the footer, but I couldn't make this feature work.

See the issue I raised on Material for MkDocs: https://github.com/squidfunk/mkdocs-material/issues/4697 and the subsequent issue I raised on the plug-in they mention: https://github.com/timvink/mkdocs-git-revision-date-localized-plugin/issues/103

It's worth updating Material for MkDocs to its latest version and check if this can now work correctly, as some time has passed since then.