Proxito: remove old implementation

[stsewd]

Mostly removing old code, there is only one small custom addition

readthedocs.org/readthedocs/proxito/views/serve.py

Lines 144 to 146 in 6595bda

	# Django doesn't include the leading slash in the path, so we normalize it here.
	path = "/" + path
	return self.serve_path(request, path)

Django doesn't capture the first slash, previously we were getting the path from request.path_info, that includes the slash! When a request is done to / the path is set to "" (empty), our code relies on that being /.

• Closes Proxito v2: Finish v2 migration and remove old implementation #10408
• Closes can't use /en/ or /zh/ as path prefix with single version #8399

How to deploy this change

• Deploy everything as usual, but don't run the projects 0105 migration!!!
• After deploy is done, run the projects 0105 migration

[humitos]

I took a quick look at this and it looks good. I didn't jump pretty deep into reviewing this code because it's mostly removal of an old implementation. I think we need to fix the tests and we are ready to go 🚀

[humitos]

Won't deploy break if we remove this field? I assume the current production code is not using this field.

[stsewd]

We need to run this migration after we have deployed the code.

[humitos]

OK! Make sure to make this pretty clear on the release project. We usually run migrations before deploying new code.