[console] deleted plan is not removed from design studio

[patelami]

Steps to reproduce:

1. Create an API using import feature:
   ap_acmetravel-0-1.json.zip
2. Create a plan > the plan will appear in the design studio(flows)
3. Delete the plan
   ** PS: This issue is only on import API feature. The plan will be deleted from design studio if the API is created from scratch**

Actual Result:
The plan still appears in the flow in design studio

Expected Result:
The plan should disappear from the flow

[phiz71]

Not able to reproduce it in 3.5.20