[ftr] skip Reporting Management on MKI (elastic#168575)

## Summary

Skipping api tests that fail on MKI 

```
Reporting
--
  | │       Reporting Management
  | │         "before each" hook for "user can not delete a report they haven't created":
  | │
  | │      ResponseError: security_exception
  | │ 	Root causes:
  | │ 		security_exception: action [indices:admin/create] is unauthorized for user [elastic] with effective roles [superuser] on restricted indices [.reporting-2020.04.19], this action is granted by the index privileges [create_index,manage,all]
  | │       at SniffingTransport.request (node_modules/@elastic/transport/src/Transport.ts:535:17)
  | │       at processTicksAndRejections (node:internal/process/task_queues:95:5)
  | │       at Indices.create (node_modules/@elastic/elasticsearch/src/api/api/indices.ts:251:12)
  | │       at attemptToCreate (create_index_stream.ts:145:9)
  | │       at handleIndex (create_index_stream.ts:211:5)
  | │       at Transform.transform [as _transform] (create_index_stream.ts:221:13)
```

x-pack/test_serverless/functional/test_suites/common/reporting/management.ts

@@ -29,6 +29,8 @@ export default ({ getPageObjects, getService }: FtrProviderContext) => {
   };
 
   describe('Reporting Management app', function () {
+    // security_exception: action [indices:admin/create] is unauthorized for user [elastic] with effective roles [superuser] on restricted indices [.reporting-2020.04.19], this action is granted by the index privileges [create_index,manage,all]
+    this.tags('failsOnMKI');
     const savedObjectsArchive = 'test/functional/fixtures/kbn_archiver/discover';
 
     const job: JobParamsCsvFromSavedObject = {