Destroying database instance with linked Clone doesn't halt on error

[mbfrahry]

Trying to destroy a database instance that has a linked clone (from snapshot)

The API returns an appropriate error, but the provider keeps re-attempting to the destroy the instance.

The destroy operation should halt after getting the error HTTP (400) Error: Linked clone service instances exist for the selected Database Cloud Service instance. Service instance can not be deleted until all the linked clone service instances are deleted.

2018-03-06T17:09:33.510-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: [DEBUG] Deleting DatabaseServiceInstance: my-terraformed-database
2018-03-06T17:09:33.510-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: go-oracle-terraform: HTTP DELETE Req (/paas/service/dbcs/api/v1.1/instances/ptstest/my-terraformed-database)
2018-03-06T17:09:34.143-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: go-oracle-terraform: Encountered HTTP (400) Error: Linked clone service instances exist for the selected Database Cloud Service instance. Service instance can not be deleted until all the linked clone service instances are deleted.
2018-03-06T17:09:34.143-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: go-oracle-terraform: 1/1 retries left
2018-03-06T17:09:34.143-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: Error during delete, waiting 30s: Error on delete (400): Linked clone service instances exist for the selected Database Cloud Service instance. Service instance can not be deleted until all the linked clone service instances are deleted.
oraclepaas_database_service_instance.database: Still destroying... (ID: my-terraformed-database, 10s elapsed)
oraclepaas_database_service_instance.database: Still destroying... (ID: my-terraformed-database, 20s elapsed)
oraclepaas_database_service_instance.database: Still destroying... (ID: my-terraformed-database, 30s elapsed)
2018-03-06T17:10:04.144-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: go-oracle-terraform: HTTP DELETE Req (/paas/service/dbcs/api/v1.1/instances/ptstest/my-terraformed-database)
2018-03-06T17:10:04.816-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: go-oracle-terraform: Encountered HTTP (400) Error: Linked clone service instances exist for the selected Database Cloud Service instance. Service instance can not be deleted until all the linked clone service instances are deleted.
2018-03-06T17:10:04.816-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: go-oracle-terraform: 1/1 retries left
2018-03-06T17:10:04.816-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: Error during delete, waiting 30s: Error on delete (400): Linked clone service instances exist for the selected Database Cloud Service instance. Service instance can not be deleted until all the linked clone service instances are deleted.
oraclepaas_database_service_instance.database: Still destroying... (ID: my-terraformed-database, 40s elapsed)
oraclepaas_database_service_instance.database: Still destroying... (ID: my-terraformed-database, 50s elapsed)
oraclepaas_database_service_instance.database: Still destroying... (ID: my-terraformed-database, 1m0s elapsed)
2018-03-06T17:10:34.818-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: go-oracle-terraform: HTTP DELETE Req (/paas/service/dbcs/api/v1.1/instances/ptstest/my-terraformed-database)
2018-03-06T17:10:35.833-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: go-oracle-terraform: Encountered HTTP (400) Error: Linked clone service instances exist for the selected Database Cloud Service instance. Service instance can not be deleted until all the linked clone service instances are deleted.
2018-03-06T17:10:35.833-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: go-oracle-terraform: 1/1 retries left
2018-03-06T17:10:35.833-0500 [DEBUG] plugin.terraform-provider-oraclepaas_v0.0.1-030621: Error during delete, waiting 30s: Error on delete (400): Linked clone service instances exist for the selected Database Cloud Service instance. Service instance can not be deleted until all the linked clone service instances are deleted.
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