fix(docs): readthedocs install (#3437)

.readthedocs.yaml

@@ -8,16 +8,18 @@ version: 2
 build:
   os: "ubuntu-22.04"
   tools:
-    python: "3.9"
+    python: "3.11"
   jobs:
     post_create_environment:
       # Install poetry
       # https://python-poetry.org/docs/#installing-manually
-      - pip install poetry
-      # Tell poetry to not use a virtual environment
-      - poetry config virtualenvs.create false
+      - python -m pip install poetry
     post_install:
-      - poetry install --only=docs
+      # Install dependencies with 'docs' dependency group
+      # https://python-poetry.org/docs/managing-dependencies/#dependency-groups
+      # VIRTUAL_ENV needs to be set manually for now.
+      # See https://github.com/readthedocs/readthedocs.org/pull/11152/
+      - VIRTUAL_ENV=${READTHEDOCS_VIRTUALENV_PATH} python -m poetry install --only=docs
 
 mkdocs:
   configuration: mkdocs.yml