improve tag regex

.github/workflows/publish_tag.yml

@@ -2,7 +2,7 @@ name: Publish to PyPI
 on:
   push:
     tags:
-      - 'v[1-9][0-9].[0-9]+.[0-9].[a-z]+'
+      - '^v[1-9][0-9]\.[0-9]+\.[0-9]\.[a-z]+$'
 
 jobs:
   pypi_release: