Use newer ubuntu and python

Author: schaefi

.github/workflows/ci-test-sdist.yml

@@ -8,10 +8,10 @@ on:
 
 jobs:
   release:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.10"]
+        python-version: ["3.11"]
 
     environment:
       name: pypi