fix TestAccComputeProjectDefaultNetworkTier_basic (#15276)

Author: shuyama1

mmv1/third_party/terraform/services/compute/resource_compute_project_default_network_tier_test.go

@@ -19,6 +19,9 @@ func TestAccComputeProjectDefaultNetworkTier_basic(t *testing.T) {
 	acctest.VcrTest(t, resource.TestCase{
 		PreCheck:                 func() { acctest.AccTestPreCheck(t) },
 		ProtoV5ProviderFactories: acctest.ProtoV5ProviderFactories(t),
+		ExternalProviders: map[string]resource.ExternalProvider{
+			"time": {},
+		},
 		Steps: []resource.TestStep{
 			{
 				Config: testAccComputeProject_defaultNetworkTier_premium(projectID, org, billingId),