Remove flaky non-e2e test (#73986)

dev/devicelab/bin/tasks/multi_widget_construction_perf__timeline_summary.dart

-// Copyright 2014 The Flutter Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-import 'package:flutter_devicelab/tasks/perf_tests.dart';
-import 'package:flutter_devicelab/framework/adb.dart';
-import 'package:flutter_devicelab/framework/framework.dart';
-
-Future<void> main() async {
-  deviceOperatingSystem = DeviceOperatingSystem.android;
-  await task(createsMultiWidgetConstructPerfTest());
-}

dev/prod_builders.json

@@ -342,12 +342,6 @@
          "task_name": "linux_multi_widget_construction_perf__e2e_summary",
          "flaky": false
       },
-      {
-         "name": "Linux multi_widget_construction_perf__timeline_summary",
-         "repo": "flutter",
-         "task_name": "linux_multi_widget_construction_perf__timeline_summary",
-         "flaky": true
-      },
       {
          "name": "Linux new_gallery__crane_perf",
          "repo": "flutter",