[FLEET] Add profiler_collector (#158436)

## Summary

Add the package
[profiler_collector](https://github.com/elastic/integrations/pull/6274)
to the list of packages that are bundled with kibana. Bundling the
profiler_collector package with kibana is required to install the
package in the Integration Server environment.

### For maintainers
- [x] This was checked for breaking API changes and was [labeled
appropriately](https://www.elastic.co/guide/en/kibana/master/contributing.html#kibana-release-notes-process)

Signed-off-by: Florian Lehner <florian.lehner@elastic.co>

fleet_packages.json

@@ -46,6 +46,12 @@
     "forceAlignStackVersion": true,
     "allowSyncToPrerelease": true
   },
+  {
+    "name": "profiler_collector",
+    "version": "8.9.0-preview",
+    "forceAlignStackVersion": true,
+    "allowSyncToPrerelease": true
+  },
   {
     "name": "synthetics",
     "version": "1.0.1"