Update update-images.yaml

Author: sirdarckcat

.github/workflows/update-images.yaml

@@ -257,7 +257,7 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v4
       with:
-        python-version: '3.5'
+        python-version: '3.7'
 
     - name: Export gcloud related env variable
       run: export CLOUDSDK_PYTHON="/usr/bin/python3"