Merge pull request #2884 from stephentoub/fixwaitallanytasktest

Fix failing TaskWaitAllAny* tests

Author: stephentoub

src/System.Threading.Tasks/tests/Task/TaskWaitAllAnyTest.cs

@@ -294,7 +294,8 @@ private void CleanUpTasks()
                 if (taskInfo.Task.Status == TaskStatus.Running)
                 {
                     taskInfo.CancellationTokenSource.Cancel();
-                    taskInfo.Task.Wait();
+                    try { taskInfo.Task.GetAwaiter().GetResult(); }
+                    catch (OperationCanceledException) { }
                 }
             }
         }