Remove @failingTest for the now passing test.

pkg/analysis_server/test/analysis/notification_errors_test.dart

Index: pkg/analysis_server/test/analysis/notification_errors_test.dart
diff --git a/pkg/analysis_server/test/analysis/notification_errors_test.dart b/pkg/analysis_server/test/analysis/notification_errors_test.dart
index 0fd3c6904a68aa9149316fb6fc93a9c960c62348..6dfc5013461c8d547eae5fedc02b9b50f086ee7a 100644
--- a/pkg/analysis_server/test/analysis/notification_errors_test.dart
+++ b/pkg/analysis_server/test/analysis/notification_errors_test.dart
@@ -162,12 +162,4 @@ class NotificationErrorsTest_Driver extends AbstractNotificationErrorsTest {
     generateSummaryFiles = true;
     super.setUp();
   }
-
-  @failingTest
-  @override
-  test_importError() {
-    // The overridden test is failing because we're getting an 'unused import'
-    // hint rather than a URI does not exist error.
-    return super.test_importError();
-  }
 }