Migrate Org. Run Task data source test

Due to the DataSource test using the Resource code to create the test
fixture we also need to update the provider factory from only the old
one to the newer Mux provider.

internal/provider/data_source_organization_run_task_test.go

@@ -26,8 +26,8 @@ func TestAccTFEOrganizationRunTaskDataSource_basic(t *testing.T) {
 	rInt := rand.New(rand.NewSource(time.Now().UnixNano())).Int()
 
 	resource.Test(t, resource.TestCase{
-		PreCheck:  func() { testAccPreCheck(t) },
-		Providers: testAccProviders,
+		PreCheck:                 func() { testAccPreCheck(t) },
+		ProtoV5ProviderFactories: testAccMuxedProviders,
 		Steps: []resource.TestStep{
 			{
 				Config: testAccTFEOrganizationRunTaskDataSourceConfig(org.Name, rInt, runTasksURL()),