Proxito: always check `404/index.hmtml` (#9983)
* Proxito: always check `404/index.hmtml`
With the introduction of `build.commands` we cannot use
`version.documentation_type` anymore since those versions will be `generic` and
we can't skip checking for this file location.
Note this commit may add and extra call to S3 API for all the 404 pages where
our regular Maze will be shown. However, it removes 2 databsae calls from all
the 404 requests.
We could only add this extra check on S3 for
`version.documentation_type='generic'`, but that would make the code a little
more complex and we won't be removing these 2 db queries.
Reference: https://github.com/readthedocs/sphinx-notfound-page/issues/215#issuecomment-1415771549
* Docs: mention `404/index.html` in hosting docs
* Proxito: get the `Version` from inside `register_page_view`
* Proxit: get the version after checking for bot score
* Proxit: call `register_page_view` just once
* Log: index file (`index.html` or `README.html`)
I'm interested in `README.html` since we should probably deprecate that "feature"
* Tests: add extra checks to make tests pass
* Lint
