[Security Solution] Add host.name and host.hostname to exceptionable Endpoint fields (#148920)

## Summary

Addresses this ticket: https://github.com/elastic/kibana/issues/148779

Allows `host.name` and `host.hostname` to be selected from the list of
available Endpoint fields.

<img width="1725" alt="image"
src="https://user-images.githubusercontent.com/56395104/212412004-0fd1bcbc-39f7-4c29-8016-7d6e8d418fb7.png">

<img width="1728" alt="image"
src="https://user-images.githubusercontent.com/56395104/212412048-826dccf1-131e-4dc2-a34d-c9f586e9e8a0.png">

Co-authored-by: Kibana Machine <42973632+kibanamachine@users.noreply.github.com>

x-pack/plugins/security_solution/public/detection_engine/rule_exceptions/utils/exceptionable_endpoint_fields.json

@@ -70,7 +70,9 @@
   "group.id",
   "host.architecture",
   "host.domain",
+  "host.hostname",
   "host.id",
+  "host.name",
   "host.os.Ext.variant",
   "host.os.family",
   "host.os.kernel",