inspector_service_test is very flaky

[kenzieschmoll]

03:44 +244 ~4 -1: /home/runner/work/devtools/devtools/packages/devtools_app/test/inspector_service_test.dart: inspector service tests track widget creation on [E]                                     
  ext.flutter.inspector.getSelectedWidget: (-32000) Service connection disposed
  dart:async                                                         _Completer.completeError
  package:devtools_app/src/eval_on_dart_library.dart 558:20          EvalOnDartLibrary.addRequest.wrappedRequest
  ===== asynchronous gap ===========================
  dart:async                                                         _asyncErrorWrapperHelper
  package:devtools_app/src/eval_on_dart_library.dart                 EvalOnDartLibrary.addRequest.wrappedRequest
  package:devtools_app/src/eval_on_dart_library.dart 582:7           EvalOnDartLibrary.addRequest
  ===== asynchronous gap ===========================
  dart:async                                                         _asyncThenWrapperHelper
  package:devtools_app/src/inspector/inspector_service.dart 686:29   ObjectGroup._callServiceExtension
  package:devtools_app/src/inspector/inspector_service.dart 714:18   ObjectGroup.invokeServiceMethodDaemonParams
  package:devtools_app/src/inspector/inspector_service.dart 677:12   ObjectGroup.invokeServiceMethodDaemonArg
  package:devtools_app/src/inspector/inspector_service.dart 719:12   ObjectGroup.invokeServiceMethodDaemonInspectorRef
  package:devtools_app/src/inspector/inspector_service.dart 952:11   ObjectGroup.invokeServiceMethodReturningNodeInspectorRef
  package:devtools_app/src/inspector/inspector_service.dart 1050:30  ObjectGroup.getSelection
  package:devtools_app/src/inspector/inspector_service.dart 386:42   InspectorService.notifySelectionChanged
  package:devtools_app/src/inspector/inspector_service.dart 410:7    InspectorService.onDebugVmServiceReceived
  ===== asynchronous gap ===========================
  dart:async                                                         _StreamImpl.listen
  package:devtools_app/src/inspector/inspector_service.dart 74:45    new InspectorService
  package:devtools_app/src/service_manager.dart 303:27               ServiceConnectionManager.vmServiceOpened
  ===== asynchronous gap ===========================
  dart:async                                                         _asyncThenWrapperHelper
  test/support/flutter_test_environment.dart 103:28                  FlutterTestEnvironment.setupEnvironment
  ===== asynchronous gap ===========================
  dart:async                                                         _asyncThenWrapperHelper
  test/inspector_service_test.dart 43:19                             main.<fn>.<fn>
  test/inspector_service_test.dart 42:40                             main.<fn>.<fn>
  
  This test failed after it had already completed. Make sure to use [expectAsync]
  or the [completes] matcher when testing async code.
  dart:async                                                         _Completer.completeError
  package:devtools_app/src/eval_on_dart_library.dart 558:20          EvalOnDartLibrary.addRequest.wrappedRequest
  ===== asynchronous gap ===========================
  dart:async                                                         _asyncErrorWrapperHelper
  package:devtools_app/src/eval_on_dart_library.dart                 EvalOnDartLibrary.addRequest.wrappedRequest
  package:devtools_app/src/eval_on_dart_library.dart 582:7           EvalOnDartLibrary.addRequest
  ===== asynchronous gap ===========================
  dart:async                                                         _asyncThenWrapperHelper
  package:devtools_app/src/inspector/inspector_service.dart 686:29   ObjectGroup._callServiceExtension
  package:devtools_app/src/inspector/inspector_service.dart 714:18   ObjectGroup.invokeServiceMethodDaemonParams
  package:devtools_app/src/inspector/inspector_service.dart 677:12   ObjectGroup.invokeServiceMethodDaemonArg
  package:devtools_app/src/inspector/inspector_service.dart 719:12   ObjectGroup.invokeServiceMethodDaemonInspectorRef
  package:devtools_app/src/inspector/inspector_service.dart 952:11   ObjectGroup.invokeServiceMethodReturningNodeInspectorRef
  package:devtools_app/src/inspector/inspector_service.dart 1050:30  ObjectGroup.getSelection
  package:devtools_app/src/inspector/inspector_service.dart 386:42   InspectorService.notifySelectionChanged
  package:devtools_app/src/inspector/inspector_service.dart 410:7    InspectorService.onDebugVmServiceReceived
  ===== asynchronous gap ===========================
  dart:async                                                         _StreamImpl.listen
  package:devtools_app/src/inspector/inspector_service.dart 74:45    new InspectorService
  package:devtools_app/src/service_manager.dart 303:27               ServiceConnectionManager.vmServiceOpened
  ===== asynchronous gap ===========================
  dart:async                                                         _asyncThenWrapperHelper
  test/support/flutter_test_environment.dart 103:28                  FlutterTestEnvironment.setupEnvironment
  ===== asynchronous gap ===========================
  dart:async                                                         _asyncThenWrapperHelper
  test/inspector_service_test.dart 43:19                             main.<fn>.<fn>
  test/inspector_service_test.dart 42:40                             main.<fn>.<fn>