Config sections in appsettings

Hi, I’m using terraform version v0.13.5 .
I’ve got a .net application and have config section in my appsettings.
I know terraform can support complex objects but it looks like appsettings only supports key value pairs, is this correct ?

  resource "azurerm_app_service" "service" {
  name                = "as-service-${var.environment}"
  https_only          = true
  location            = var.azure-location
  resource_group_name = var.resource-group-name
  app_service_plan_id = azurerm_app_service_plan.syndication-service.id
  app_settings        = {
                   ClientCertificate = {
                              Organization = "organization"
                              OrganizationalUnit = "unit"
                              Required= true
                              Subject= "subject",
                              Thumbprint= "thumbprint"
                        }
}
}