Suppress some python-version warnings

Author: David Robertson

.github/workflows/tests.yml

@@ -33,6 +33,8 @@ jobs:
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-python@v4
+        with:
+          python-version: "3.x"
       - uses: matrix-org/setup-python-poetry@v1
         with:
           extras: "all"
@@ -44,6 +46,8 @@ jobs:
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-python@v4
+        with:
+          python-version: "3.x"
       - run: "pip install 'click==8.1.1' 'GitPython>=3.1.20'"
       - run: scripts-dev/check_schema_delta.py --force-colors
 
@@ -68,6 +72,8 @@ jobs:
           ref: ${{ github.event.pull_request.head.sha }}
           fetch-depth: 0
       - uses: actions/setup-python@v4
+        with:
+          python-version: "3.x"
       - run: "pip install 'towncrier>=18.6.0rc1'"
       - run: scripts-dev/check-newsfragment.sh
         env: