chore(workflows): post mock diff md comment for demo purposes

.github/workflows/comment-preview.yml

@@ -0,0 +1,17 @@
+on: push
+
+permissions:
+  pull-requests: write
+
+jobs:
+  example_comment_pr:
+    runs-on: ubuntu-latest
+    name: An example job to comment a PR
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Comment PR
+        uses: thollander/actions-comment-pull-request@v2
+        with:
+          filePath: packages/utils/src/lib/reports/__snapshots__/report-diff-mixed.md
+          pr_number: 566