Build docs on python 3.10

Signed-off-by: Johannes Mueller <[email protected]>

.github/workflows/docs-gh-pages.yml

@@ -23,7 +23,7 @@ concurrency:
 jobs:
   build-docs:
     runs-on: [ubuntu-latest]
-    container: python:3-buster
+    container: python:3.10-buster
     steps:
       - uses: actions/checkout@v3
       - name: Install dependencies