[BUG]Not able to remove gateways after removing it from the code.

### Release version

v6.0.1.1

### Describe the bug

In the api code, if we add the gateway, we are able to see the gateway in apim.
If we delete the gateway in api code, the gateway is not getting deleted.

### Expected behavior

Under artifacts -> gateways -> gateway name -> apis -> yourapi --> Gateway is added in apim api collection..
Under artifacts -> gateways -> gateway name -> apis -> yourapi [remove this one] --> Gateway should be removed from apim api collection

### Actual behavior

Under artifacts -> gateways -> gateway name -> apis -> yourapi --> Gateway is added in apim api collection.. [working as expected]
Under artifacts -> gateways -> gateway name -> apis -> yourapi [remove this one] --> Gateway is not getting removed from apim api collection

### Reproduction Steps

Under artifacts -> gateways -> gateway name -> apis -> yourapi --> Gateway is added in apim api collection.. [working as expected]
Under artifacts -> gateways -> gateway name -> apis -> yourapi [remove this one] --> Gateway is not getting removed from apim api collection

Beginnen Sie damit, das Problem in Release v6.0.1.1 anhand des beschriebenen artifacts → gateways → gateway name → apis-Pfads zu reproduzieren, und bestätigen Sie zunächst, dass das Hinzufügen des Gateways die APIM API-Sammlung aktualisiert. Verfolgen Sie die Behandlung der Entfernung und überprüfen Sie, dass das Löschen der API-Referenz dazu führt, dass das Gateway aus der APIM API-Sammlung verschwindet.

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