only release on certain tag conventions

.github/workflows/release.yml

@@ -1,9 +1,9 @@
-# Terraform Provider release workflow.
 name: Release
 
 on:
   push:
     tags:
+      - "v[0-9]+.[0-9]+.[0-9]+"
 
 # Releases need permissions to read and write the repository contents.
 # GitHub considers creating releases and uploading assets as writing contents.