Had it backwards, the problem is with Drutopia under-specifying so the
simple way that used to work no longer does. Ridiculous that
ReadTheDocs makes us specify the build operating system as if we
flipping care 99% of the time.
This reverts commit 6611ee36a1.
Error
Problem in your project's configuration. Invalid python.version: .readthedocs.yml: Invalid configuration option: python.version. Make sure the key name is correct.
Error
Problem in your project's configuration. Invalid build.tools.python: .readthedocs.yml: Invalid configuration option: build.tools.python. Make sure the key name is correct.