more fixes for RTD

.github/workflows/github-actions.yml

@@ -115,6 +115,8 @@ jobs:
   build_doc_dryrun:
     # ensures that readthedocs can be built continuously
     # to avoid that it breaks when new releases are being created
+    # The way RTD works is that it builds the doc on its side
+    # builds are visible at https://readthedocs.org/projects/mongoengine-odm/builds/
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v3

.readthedocs.yml

@@ -11,7 +11,6 @@ sphinx:
 
 # Optionally set the version of Python and requirements required to build your docs
 python:
-  version: 3.9
   install:
     - requirements: docs/requirements.txt
     # docs/conf.py is importing mongoengine