.github/workflows/main.yml: Test 3.13-dev

Author: Matthias Koeppe

Diff for: .github/workflows/main.yml

@@ -17,7 +17,7 @@ jobs:
             fail-fast: false
             matrix:
                 os: [ubuntu-latest, macos-latest, windows-latest]
-                python-version: ['3.8', '3.9', '3.10', '3.11.6', '3.12.0']
+                python-version: ['3.8', '3.9', '3.10', '3.11', '3.12', '3.13-dev']
                 architecture: [x64, x86]
                 exclude:
                     - os: ubuntu-latest