Reinstate Ubuntu 18 and drop Python 3.6 and 3.7

3.7 is not available anymore on newer OSes and is retired in 2023.

Signed-off-by: Philippe Ombredanne <[email protected]>

Author: pombredanne

azure-pipelines.yml

@@ -9,48 +9,56 @@ jobs:
 
     - template: etc/ci/azure-posix.yml
       parameters:
-          job_name: ubuntu22_cpython
-          image_name: ubuntu-22.04
-          python_versions: ['3.6', '3.7', '3.8', '3.9', '3.10']
+          job_name: ubuntu18_cpython
+          image_name: ubuntu-18.04
+          python_versions: ['3.7', '3.8', '3.9', '3.10']
           test_suites:
               all: venv/bin/pytest -n 2 -vvs
 
     - template: etc/ci/azure-posix.yml
       parameters:
           job_name: ubuntu20_cpython
           image_name: ubuntu-20.04
-          python_versions: ['3.6', '3.7', '3.8', '3.9', '3.10']
+          python_versions: ['3.8', '3.9', '3.10', '3.11']
+          test_suites:
+              all: venv/bin/pytest -n 2 -vvs
+
+    - template: etc/ci/azure-posix.yml
+      parameters:
+          job_name: ubuntu22_cpython
+          image_name: ubuntu-22.04
+          python_versions: ['3.8', '3.9', '3.10', '3.11']
           test_suites:
               all: venv/bin/pytest -n 2 -vvs
 
     - template: etc/ci/azure-posix.yml
       parameters:
           job_name: macos12_cpython
           image_name: macos-12
-          python_versions: ['3.6', '3.7', '3.8', '3.9', '3.10']
+          python_versions: ['3.8', '3.9', '3.10', '3.11']
           test_suites:
               all: venv/bin/pytest -n 2 -vvs
 
     - template: etc/ci/azure-posix.yml
       parameters:
           job_name: macos11_cpython
           image_name: macos-11
-          python_versions: ['3.7', '3.8', '3.9', '3.10']
+          python_versions: ['3.8', '3.9', '3.10', '3.11']
           test_suites:
               all: venv/bin/pytest -n 2 -vvs
 
     - template: etc/ci/azure-win.yml
       parameters:
           job_name: win2019_cpython
           image_name: windows-2019
-          python_versions: ['3.6', '3.7', '3.8', '3.9', '3.10']
+          python_versions: ['3.8', '3.9', '3.10', '3.11']
           test_suites:
               all: venv\Scripts\pytest -n 2 -vvs
 
     - template: etc/ci/azure-win.yml
       parameters:
           job_name: win2022_cpython
           image_name: windows-2022
-          python_versions: ['3.7', '3.8', '3.9', '3.10']
+          python_versions: ['3.8', '3.9', '3.10', '3.11']
           test_suites:
               all: venv\Scripts\pytest -n 2 -vvs