updating readthedocs image to os

.readthedocs.yaml

@@ -4,6 +4,11 @@ version: 2
 formats:
    - pdf
 
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3.11"
+
 # Build documentation in the docs/ directory with Sphinx
 sphinx:
    configuration: docs/source/conf.py