configure RTD to use poetry

.readthedocs.yml

@@ -4,11 +4,21 @@ build:
   os: ubuntu-22.04
   tools:
     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
+    post_install:
+      # Install dependencies with 'docs' dependency group
+      # https://python-poetry.org/docs/managing-dependencies/#dependency-groups
+      - poetry install --with docs
 
 python:
   install:
     - requirements: docs/requirements.txt
-    - requirements: requirements.txt
 
 sphinx:
   builder: html

pyproject.toml

@@ -49,6 +49,12 @@ codecov = ">=2.1.12"
 pytest-cov = "^4.1.0"
 pre-commit = ">=3.3.2"
 
+[tool.poetry.group.docs]
+optional = true
+
+[tool.poetry.group.docs.dependencies]
+mkdocs = "*"
+
 [build-system]
 requires = ["poetry-core"]
 build-backend = "poetry.core.masonry.api"