Provider perpetually tries to add encryption_key on GCP instances despite null value

[jamiezieziula]

Environment:

• Terraform ClickHouse Provider Version: 3.8.0
• Cloud Provider: GCP
• Affected Tier: Development instances

Description

When running Terraform apply against a development ClickHouse service, the provider consistently attempts to add the encryption_key attribute on every plan, even if I explicitly set the value to null in the configuration. This does not occur on production instances with identical configuration.

Configuration

resource "clickhouse_service" "clickhouse" {
  name           = "dev"
  cloud_provider = "gcp"
  region         = "us-east1"
  tier           = "development"

  encryption_key = null  # Explicitly set to null, but still shows in plan
}

or

resource "clickhouse_service" "clickhouse" {
  name           = "dev"
  cloud_provider = "gcp"
  region         = "us-east1"
  tier           = "development"
}

Expected Behavior

Since the ClickHouse API returns null for encryption_key on GCP instances (the attribute is only relevant for AWS), explicitly setting encryption_key = null should prevent Terraform from detecting drift or attempting to add this attribute.

Actual Behavior

On every terraform plan or terraform apply, the provider shows:

+ encryption_key = null