Handle deletion when the underlying GCP resource does not exist

[gemmahou]

Checklist

• I did not find a related open enhancement request.
• I understand that enhancement requests filed in the GitHub repository are by default low priority.
• If this request is time-sensitive, I have submitted a corresponding issue with GCP support.

Describe the feature or resource

If the underlying GCP resource does not exist, the krm resource should be able to be deleted too.

We have a recent improvement to address this #3656, in apigee, firestore, sql and workstation controllers and the controller template.

Another option is to reuse the existAlready flag(code) to avoid making deletion request to GCP if we know the underlying resource does not exist, and prevent making changes to individual controllers.

Additional information

No response

Importance

No response