pinning publish version to 3.9

Author: eric-fichtel-adobe

.github/workflows/publish.yml

@@ -18,7 +18,7 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v2
       with:
-        python-version: '^3.9'
+        python-version: '3.9'
     - name: Install dependencies
       env:
         CI: true