github: build on Python 3.13

Author: dlech

.github/workflows/test.yml

@@ -28,7 +28,7 @@ jobs:
     runs-on: ubuntu-22.04
     strategy:
       matrix:
-        python-version: [ '3.10', '3.11', '3.12' ]
+        python-version: [ '3.10', '3.11', '3.12', '3.13' ]
     steps:
       - run: pipx install poetry
       - uses: actions/setup-python@v4