Restore the pull request trigger event

Signed-off-by: Peter Zhu <[email protected]>

.github/workflows/build-test.yml

@@ -5,8 +5,7 @@ on:
   push:
     branches:
       - 'main'
-  pull_request_target:
-    types: [opened, synchronize, reopened]
+  pull_request:
 
 jobs:
   build-test:
@@ -19,11 +18,6 @@ jobs:
     if: github.repository == 'opensearch-project/automation-app'
     steps:
       - uses: actions/checkout@v4
-        if: github.event_name == 'push'
-      - uses: actions/checkout@v4
-        if: github.event_name == 'pull_request' || github.event_name == 'pull_request_target'
-        with:
-          ref: ${{ github.event.pull_request.head.sha }}
       - name: Set up node-${{ matrix.node-version }}
         uses: actions/setup-node@v4
         with: