ci: enable ci on release branches

Author: hfudev

.github/workflows/test-python.yml

@@ -8,7 +8,7 @@ on:
       - .github/workflows/test-python.yml
       - "!docs/**"
   push:
-    branches: [main]
+    branches: [release/*, main]
 
 # cancel jobs if new commit pushed
 concurrency: