build: run tests on 3.12

...and use pre-releases if needed

Author: nedbat

.github/workflows/coverage.yml

@@ -48,6 +48,7 @@ jobs:
           - "3.9"
           - "3.10"
           - "3.11"
+          - "3.12"
           - "pypy-3.7"
           - "pypy-3.8"
           - "pypy-3.9"
@@ -77,6 +78,7 @@ jobs:
         uses: "actions/setup-python@v4"
         with:
           python-version: "${{ matrix.python-version }}"
+          allow-prereleases: true
           cache: pip
           cache-dependency-path: 'requirements/*.pip'
 

.github/workflows/testsuite.yml

@@ -49,6 +49,7 @@ jobs:
           - "3.9"
           - "3.10"
           - "3.11"
+          - "3.12"
           - "pypy-3.7"
           - "pypy-3.9"
         exclude:
@@ -65,6 +66,7 @@ jobs:
         uses: "actions/setup-python@v4"
         with:
           python-version: "${{ matrix.python-version }}"
+          allow-prereleases: true
           cache: pip
           cache-dependency-path: 'requirements/*.pip'