ci: systematic use of ubuntu 22.04 and python 3.11

.github/workflows/publish.yml

@@ -34,7 +34,7 @@ jobs:
   # ref: https://hub.docker.com/orgs/jupyterhub
 
   publish:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v3
         with:
@@ -44,7 +44,7 @@ jobs:
 
       - uses: actions/setup-python@v4
         with:
-          python-version: "3.8"
+          python-version: "3.11"
 
       - name: Decide to publish or not
         id: publishing

.github/workflows/release-tag.yml

@@ -9,7 +9,7 @@ on:
 
 jobs:
   create-release:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     permissions:
       contents: write
     steps:

.github/workflows/support-bot.yml

@@ -10,7 +10,7 @@ permissions:
 
 jobs:
   action:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: dessant/support-requests@v3
         with:

.github/workflows/test-docker-build.yaml

@@ -29,7 +29,7 @@ jobs:
   # - https://github.com/docker/build-push-action/blob/v2.3.0/docs/advanced/local-registry.md
   # - https://github.com/docker/build-push-action/blob/v2.3.0/docs/advanced/multi-platform.md
   build_images:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v3
         with:

.github/workflows/test-docs.yaml

@@ -25,7 +25,7 @@ on:
 
 jobs:
   linkcheck:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v3
         with:

.github/workflows/vuln-scan.yaml

@@ -32,7 +32,7 @@ on:
 jobs:
   trivy_image_scan:
     if: github.repository == 'jupyterhub/zero-to-jupyterhub-k8s'
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     environment: watch-dependencies
 
     strategy:

.github/workflows/watch-dependencies.yaml

@@ -32,7 +32,7 @@ jobs:
   update-image-dependencies:
     # Don't run this job on forks
     if: github.repository == 'jupyterhub/zero-to-jupyterhub-k8s'
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     environment: watch-dependencies
 
     strategy:
@@ -202,7 +202,7 @@ jobs:
     # these dependencies every day is too much noise.
     #
     if: github.repository == 'jupyterhub/zero-to-jupyterhub-k8s' && github.event_name != 'schedule'
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     environment: watch-dependencies
 
     steps: