Chore/fix workflow sha (#807)

* checkout merge commit of PR, not base branch head

https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#pull_request_target

* use link to test result, gif exceeds github allowed content length

.github/workflows/tests.yml

@@ -12,6 +12,8 @@ jobs:
       options: --user root
     steps:
       - uses: actions/checkout@v4
+        with:
+          ref: '${{ github.event.pull_request.merge_commit_sha }}' # since event is pull_request_target
       - name: Install Packages
         run: yarn install --frozen-lockfile
       - name: Build
@@ -35,4 +37,4 @@ jobs:
       - name: Show URL
         run: echo '${{ steps.upload.outputs.file-url }}'
         id: artifact-upload-step
-      - run: echo '![test](${{ steps.upload.outputs.file-url }})' >> $GITHUB_STEP_SUMMARY
+      - run: echo '<picture><img src="${{ steps.upload.outputs.file-url }}"></picture>' >> $GITHUB_STEP_SUMMARY