Update RTD config

This should fix #877.

Author: jezdez

.readthedocs.yml

@@ -2,15 +2,17 @@ version: 2
 
 # Set the version of Python and other tools you might need
 build:
-  os: ubuntu-20.04
+  os: ubuntu-22.04
   tools:
     python: "3.12"
 
 python:
   install:
   # Install dependencies from setup.py .
-    - method: setuptools
+    - method: pip
       path: .
+      extra_requirements:
+        - dev
 
 # Build documentation in the docs/ directory with Sphinx
 sphinx: