infra: support new ubuntu 22.04 runners.

Inverted logic from before. Run all python versions on 22.04.  Do not
run any except 3.6 and 3.11 on 20.04.

Python 3.6 is not and will not be available on 22.04.

Also run 3.12-dev on 22.04.

Author: rouilj

.github/workflows/ci-test.yml

@@ -45,36 +45,36 @@ jobs:
       max-parallel: 4
       matrix:
         # Run in all these versions of Python
-        python-version: [ "2.7", "3.10", "3.9", "3.8", "3.6", "3.11-dev" ]
+        python-version:
+          - "2.7"
+          - "3.10"
+          - "3.9"
+          - "3.8"
+          - "3.7"
+          - "3.11"
 
         # use for multiple os or ubuntu versions
         #os: [ubuntu-latest, macos-latest, windows-latest]
-        os: [ubuntu-latest, ubuntu-22.04]
+        # ubuntu latest 22.04 12/2022
+        os: [ubuntu-latest, ubuntu-20.04]
 
         # if the ones above fail. fail the build
         experimental: [false]
 
         include:
             # example: if 3.12 fails the jobs still succeeds
-            - python-version: 3.12.0-alpha
+            - python-version: 3.12-dev
               os: ubuntu-22.04
               experimental: [true]
-            # version 2.7 not available on unbuntu-22.04 github
-            #- python-version: 2.7
-            #  os: ubuntu-22.04
-            #  experimental: true
             - python-version: 3.11-dev
-              os: ubuntu-22.04
-              experimental: [true]
-            # Fail the run if these fail
-            #- python-version: 3.6
-            #  os: ubuntu-20.04
-            #- python-version: 2.7
-            #  os: ubuntu-20.04
+              os: ubuntu-20.04
+            # 3.6 not available on new 22.04 runners, so run on 20.04 ubuntu
+            - python-version: 3.6
+              os: ubuntu-20.04
 
         exclude:
-            # skip all python versions on 22.04 except explicitly included
-            - os: ubuntu-22.04
+            # skip all python versions on 20.04 except explicitly included
+            - os: ubuntu-20.04
 
     env:
       # get colorized pytest output even without a controlling tty