[Entity Analytics] Ensuring definition transforms are managed (#193408)

## Summary

This PR adds the `managed` flag to the entity definitions so that the
generated transforms are tagged as such.

### How to test

1. Add `EntityStoreEnabled` feature flag to your `kibana.dev.yml`
2. Call `POST kbn:/api/entity_store/engines/<user | host>/init` with an
empty (`{}`) body.
3. Go to `Stack Management > Transforms` and verify that the 2 new
transforms are tagged as managed

Implements elastic/security-team#10608

---------

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

x-pack/plugins/security_solution/server/lib/entity_analytics/entity_store/definition.ts

@@ -32,6 +32,7 @@ export const buildHostEntityDefinition = (space: string): EntityDefinition =>
       interval: '1m',
     },
     version: '1.0.0',
+    managed: true,
   });
 
 export const buildUserEntityDefinition = (space: string): EntityDefinition =>
@@ -47,4 +48,5 @@ export const buildUserEntityDefinition = (space: string): EntityDefinition =>
       interval: '1m',
     },
     version: '1.0.0',
+    managed: true,
   });