Update publish-to-dafni.yaml

fix: quotation marks in python-version

Author: f-allian

.github/workflows/publish-to-dafni.yaml

@@ -36,7 +36,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: actions/setup-python@v3
         with:
-          python-version: 3.10
+          python-version: '3.10'
 
       - name: Build the container
         run: |