Sphynx document on Github pages Needs `.nojekyll` File

I recently tried to upload the Linux kernel document which is generated in html form using the Sphynx build system[1] on a Github page[2] so that people can read DAMON[3] document from everywhere. The upload was very easy. I simply created the repo, put the generated html doc at Documentation/output/ into the repo and pushed. However, the theme was not applied. Github assumes every Github pages to be based on Jekyll[4], and because every files and directories starting with underscores are handled special in Jekyll, some directories Sphynx created were ignored.