Update noetic-docker-build-check.yml

.github/workflows/noetic-docker-build-check.yml

@@ -1,7 +1,7 @@
 name: ROS-noetic Docker Build Check
 
 on:
-  pull_request_target:
+  pull_request:
   workflow_dispatch:
 
 jobs:
@@ -13,17 +13,10 @@ jobs:
         run: rm -rf /opt/hostedtoolcache
       - name: checkout
         uses: actions/checkout@v2
-        with:
-          ref: ${{ github.event.pull_request.head.sha }}
       - name: set up QEMU
         uses: docker/setup-qemu-action@v1
       - name: set up Docker Buildx
         uses: docker/setup-buildx-action@v1
-      - name: login to DockerHub
-        uses: docker/login-action@v1
-        with:
-          username: ${{ secrets.DOCKERHUB_USERNAME }}
-          password: ${{ secrets.DOCKERHUB_TOKEN }}
       - name: build check
         uses: docker/build-push-action@v2
         with: