Refguide checking update merged

PSA: Now that ENH/TST: Refactor refguide-check, take 3 by ev-br · Pull Request #20127 · scipy/scipy · GitHub is merged, the way to to check the examples in the documentation is

$ pip install scipy-doctest # once

This checks docstrings of public objects:

$ python smoke-docs accepts usual subcommands, -s submodule, -t path/to/file etc

This checks the ReST tutorials in the doc/source/tutorial directory:

$ python smoke-tutorials

For those who prefer to avoid and use pytest directly:

$ pytest --doctest-modules path/to/file/or/directory --other-pytest-switches-as-desired