Add link to +main, +nightly manifest in CI bot comment (#8384)

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Co-authored-by: Jan Procházka <[email protected]>

Author: grtlr

.github/workflows/reusable_upload_web.yml

@@ -151,9 +151,9 @@ jobs:
 
             - [ ] I have tested the web viewer
 
-            | Result | Commit  | Link  |
-            | ------ | ------- | ----- |
-            | ✅ | ${{ steps.get-sha.outputs.sha }} | https://rerun.io/viewer/pr/${{ github.event.pull_request.number }} |
+            | Result | Commit  | Link | Manifest |
+            | ------ | ------- | ---- | -------- |
+            | ✅ | ${{ steps.get-sha.outputs.sha }} | https://rerun.io/viewer/pr/${{ github.event.pull_request.number }} | [+nightly](https://rerun.io/viewer/pr/${{ github.event.pull_request.number }}?manifest_url=https://app.rerun.io/version/nightly/examples_manifest.json) [+main](https://rerun.io/viewer/pr/${{ github.event.pull_request.number }}?manifest_url=https://app.rerun.io/version/main/examples_manifest.json) |
 
             <sup>Note: This comment is updated whenever you push a commit.</sup>