If you still looking for it, you whould use the resource "databricks_access_control_rule_set"

Something like that :

resource "databricks_service_principal" "sp" {
  display_name = "ndp-sp-${var.project}-${lower(var.env)}"
}

resource "databricks_access_control_rule_set" "automation_sp_rule_set" {
  name = "accounts/{account-id}/servicePrincipals/${databricks_service_principal.sp.application_id}/ruleSets/default"

  grant_rules {
    principals = [data.databricks_group.admin_group.id]
    role       = "roles/servicePrincipal.manager"
  }
}