Get technical user for managed connector details api

[dhiren-singh-007]

API : GET: /api/administration/connectors/{connectorId}

Current Behavior

For owned connectors there is direct linking of technical user so this api returns the technical user.
While for managed connector there is indirect linking of technical user via App/Service subscription and this api don't return the technical user .

Expected Behavior

For managed connector this api should return the technical user as it will be convenient for customer/host to see the Connector technical user in connector details view. It should show the technical user which is created on activation of subscription and used to create the managed connector.

Steps To Reproduce

1. Create a Managed connector
2. Now click on details arrow in Managed connector list
3. It will show "No technical user available"

Owned connector detail view:

Managed connector detail view :