docs: fix readthedocs build

.readthedocs.yaml

@@ -4,7 +4,11 @@ build:
   os: "ubuntu-20.04"
   tools:
     python: "3.10"
-
-python:
-  install:
-    - requirements: docs-requirements.txt
+  jobs:
+    pre_create_environment:
+      - asdf plugin add poetry
+      - asdf install poetry latest
+      - asdf global poetry latest
+      - poetry config virtualenvs.create false
+    post_install:
+      - poetry install -E docs