ci: update readthedocs.yaml

.readthedocs.yaml

@@ -9,9 +9,7 @@ build:
     python: "3.10"
 
   jobs:
-    post_create_environment:
+    post_install:
       - pip install poetry
       - poetry config virtualenvs.create false
-
-    post_install:
       - pip install --user --requirement < poetry export --only doc --format requirements.txt