Update readthedocs config

.readthedocs.yml

@@ -12,10 +12,9 @@ build:
   jobs:
     post_create_environment:
       - pip install poetry
-      - poetry config virtualenvs.create false
     post_install:
-      - poetry install --with docs
+      - VIRTUAL_ENV=$READTHEDOCS_VIRTUALENV_PATH poetry install --with docs
 
 # Build documentation in the "docs/" directory with Sphinx
-sphinx:
-  configuration: docs/source/conf.py
+mkdocs:
+  configuration: mkdocs.yml