harbor_project resource updates storage_quota in state file although no change is made in Harbor

[nasseredine]

Describe the bug
Using a robot account with the provider results in the storage_quota from harbor_project resource being updated in the Terraform state although no change is made in Harbor. No error is thrown.

To Reproduce

1. Create a robot account regardless of its permissions.

2. Export environnent variables:

export HARBOR_USERNAME=<harbor-robot-account-name>
export HARBOR_PASSWORD=<harbor-robot-account-password>
export HARBOR_URL=<harbor-url>

3. Write a main.tf configuration file:

terraform {
  required_providers {
    harbor = {
      source  = "goharbor/harbor"
      version = "3.10.15"
    }
  }
}

resource "harbor_project" "foo" {
  name          = "foo"
  storage_quota = 1
}

4. Initiliaze Terraform working dir and create the foo project with a storage_quota of 1:

terraform init
terraform apply --auto-approve

5. Update the storage_quota value to 2 and apply the changes:

sed -rE 's/^(\s+storage_quota\s*=) [0-9]+$/\1 2/g' -i main.tf
terraform apply --auto-approve

6. Verify the storage_quota in the Terraform state file and compare the value with the one in Harbor Project Quotas:

cat terraform.tfstate | grep storage_quota

Expected behavior

• Terraform apply command must result in a failure with an error message.
• The storage_quota must not be updated in the Terraform state.

Additional context
Robot account permissions are limited and don't allow the update of a quota. See issue: goharbor/harbor#20076 (comment)
Only admin user accounts can update the quota

• Provider Version 3.10.15
• Terraform Version 1.9.6
• Harbor Version 2.10.0