ci; use check-latest: true for -dev pythons

When testing -dev python versions, we want to always use the latest.

Author: bluetech

.github/workflows/test.yml

@@ -179,6 +179,7 @@ jobs:
       uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python }}
+        check-latest: ${{ endsWith(matrix.python, '-dev') }}
 
     - name: Install dependencies
       run: |