Add security_detection_engine into exclude list for observability pro…

…jects (#184022)

## Summary

Include [`security_detection_engine`
package](https://github.com/elastic/integrations/tree/d2a74171c8fc32fd8754af0a2dd733669b5f6578/packages/security_detection_engine)
into the list of excluded packages for Observability projects in Elastic
Serverless.

Relates elastic/integrations#9849
Relates elastic/integrations#9938


### 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)

Co-authored-by: Kibana Machine <[email protected]>

config/serverless.oblt.yml

@@ -53,6 +53,7 @@ xpack.fleet.internal.registry.excludePackages: [
     # Security integrations
     'endpoint',
     'beaconing',
+    'security_detection_engine',
 
     # Removed in 8.11 integrations
     'cisco',