Ensure advanced threat protection is used for Azure MySQL Single Server

Disabled advanced threat protection may make Azure MySQL Server susceptible to various attacks.

In Azure Console -

1. Open the Azure Portal and go to SQL Servers.
2. Select the MySQL Server you wish to edit.
3. Under Security, select Microsoft Defender for Cloud.
4. Configure as needed.

In Terraform -

1. In the azurerm_mysql_server resource, under threat_detection_policy, set enabled to true.

References:
https://learn.microsoft.com/en-us/azure/azure-sql/database/threat-detection-configure?view=azuresql
https://registry.terraform.io/providers/hashicorp/azurerm/latest/docs/resources/mysql_server#email_account_admins