pin python 3.12 for publish

Author: Phil Varner

.github/workflows/python-publish.yml

@@ -24,7 +24,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
-          python-version: "3.x"
+          python-version: "3.12"
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip