ci: unit test on v2 branch

Author: sxzz

.github/workflows/unit-test.yml

@@ -2,9 +2,9 @@ name: Unit Test
 
 on:
   push:
-    branches: [main]
+    branches: [main, v2]
   pull_request:
-    branches: [main]
+    branches: [main, v2]
 
 permissions: {}