[llvm] Reapply [workflows] Split pr-code-format into two parts to make it more secure (#78215) (PR #80495)

[Tom Stellard via llvm-commits]

================
@@ -0,0 +1,122 @@
+name: Comment on an issue
+
+on:
+  workflow_run:
+    workflows: ["Check code formatting"]
+    types:
+      - completed
+
+permissions:
+  contents: read
+
+jobs:
+  pr-comment:
+    runs-on: ubuntu-latest
+    permissions:
+      pull-requests: write
+    if: >
+      github.event.workflow_run.event == 'pull_request'
+    steps:
+      - name: 'Download artifact'
+        uses: actions/download-artifact at 6b208ae046db98c579e8a3aa621ab581ff575935 # v4.1.1
+        with:
+          github-token: ${{ secrets.ISSUE_WRITE_DOWNLOAD_ARTIFACT }}
+          run-id: ${{ github.event.workflow_run.id }}
+          name: workflow-args
+
+      - name: 'Comment on PR'
+        uses: actions/github-script at v3
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          script: |
+            var fs = require('fs');
+            const comments = JSON.parse(fs.readFileSync('./comments'));
+            if (!comments) {
+              return;
+            }
+
+            let runInfo = await github.actions.getWorkflowRun({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              run_id: context.payload.workflow_run.id
+            });
+
+            console.log(runInfo);
+
+
+            // Query to find the number of the pull request that triggered this job.
----------------
tstellar wrote:

The associated pull requests are based off of the branch name, so if you create a pull request for a branch, close it, and then create another pull request with the same branch, then this query will return two associated pull requests.

https://github.com/llvm/llvm-project/pull/80495