Link to app.rerun.io from examples page (rerun-io#5201)

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* Using newly built examples:
[app.rerun.io](https://app.rerun.io/pr/5201/index.html)
* Using examples from latest `main` build:
[app.rerun.io](https://app.rerun.io/pr/5201/index.html?manifest_url=https://app.rerun.io/version/main/examples_manifest.json)
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- [PR Build Summary](https://build.rerun.io/pr/5201)
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<!--DOCS-PREVIEW-->
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preview](https://rerun.io/preview/31f988054fad9edd9f033385d574d1338cda554c/examples)
<!--EXAMPLES-PREVIEW-->
- [Recent benchmark results](https://build.rerun.io/graphs/crates.html)
- [Wasm size tracking](https://build.rerun.io/graphs/sizes.html)

examples/manifest.toml

@@ -9,6 +9,8 @@ They all require additional data to be downloaded, so an internet connection is
 Each example downloads it's own data, so no additional steps are needed.
 For the simplest possible examples showing how to use each api,
 check out [Types](/docs/reference/types).
+
+You can try these examples live at <https://app.rerun.io/>.
 """
 examples = [
   "arkit_scenes",