Build documentation with Bazel

[nahueespinosa]

Feature description

Currently, we rely on a Makefile and scripts to generate documentation. These tools have a list of Python requirements and system dependencies. Bazel can probably do a better job in terms of dependency tracking and incremental changes without having to spin up a container to generate docs.

Implementation considerations

rules_python comes with rules to generate sphinx docs: https://rules-python.readthedocs.io/en/latest/sphinxdocs/index.html#

While it is primarily oriented towards docgen for Starlark code, the core of it is agnostic as to what is being documented.

EDIT: The clanky bits have more to do with doxygen than make.

[hidmic]

I like the idea.