Update/fix read the docs config

Signed-off-by: Pedro Algarvio <[email protected]>

.readthedocs.yaml

@@ -7,26 +7,22 @@ version: 2
 
 # Set the version of Python and other tools you might need
 build:
-  os: ubuntu-20.04
+  os: ubuntu-22.04
   tools:
     python: "3.9"
-    # You can also specify other tool versions:
-    # nodejs: "16"
-    # rust: "1.55"
-    # golang: "1.17"
 
 # Build documentation in the docs/ directory with Sphinx
 sphinx:
-   configuration: docs/conf.py
+  configuration: docs/conf.py
+  fail_on_warning: true
 
-# If using Sphinx, optionally build your docs in additional formats such as PDF
+# Optionally build your docs in additional formats such as PDF
 formats:
   - pdf
 
-# Optionally declare the Python requirements required to build your docs
+# Optionally set the version of Python and requirements required to build your docs
 python:
   install:
     - method: pip
       path: .
-      extra_requirements:
-        - docs
+    - requirements: requirements/docs.txt