ci: readthedocs

- Use "version: 2" config so we can use newer python.
- Fail on sphinx warnings.

Author: justinmk

.readthedocs.yml

@@ -1,6 +1,23 @@
+# readthedocs config file for Sphinx projects
+# https://docs.readthedocs.io/en/stable/config-file/v2.html
+
+# Required
+version: 2
+
+# Set the OS, Python version and other tools you might need
 build:
-  image: latest
+  os: ubuntu-22.04
+  tools:
+    python: "3.11"
+
+# Build documentation in the "docs/" directory with Sphinx
+sphinx:
+  configuration: docs/conf.py
+  # Fail on all warnings.
+  fail_on_warning: true
 
 python:
-  version: 3.8
-  setup_py_install: true
+   install:
+   - requirements: docs/requirements.txt
+   - method: pip
+     path: .