ci: deploy vercel on all PRs

Author: JounQin

.github/workflows/vercel.yml

@@ -4,9 +4,7 @@ on:
   push:
     branches:
       - master
-  pull_request_target:
-    branches:
-      - master
+  pull_request: null
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}