Update python-build.yml

Author: Chenglong-MS

.github/workflows/python-build.yml

@@ -46,7 +46,7 @@ jobs:
     runs-on: ubuntu-latest
     needs:
       - build
-    if: github.event_name == 'push'
+    if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags')
     environment:
       name: pypi
       url: https://pypi.org/p/data-formulator