Aha! Much simpler than my workaround. Thanks @bep
EDIT
However in the static folder the Let’s Encrypt token needs to be saved as a .html file and specifying the token’s URL with front matter does not work.
One will have to replicate the required path structure with folders. So it really depends on what one thinks will be best for maintenance. A couple of empty sections and corresponding .md files or a bunch of nested folders in /static/ .
2nd EDIT
If one uses my approach instead of the suggestion made by @bep it will be necessary to exclude the Let’s Encrypt pages from the sitemap.xml see this thread for more info: