FileSystemWatcher tests fail intermittently on Unix due to too many open inotify instances #16208
Description
http://dotnet-ci.cloudapp.net/job/dotnet_corefx/job/centos7.1_release_tst_prtest/1094/console
19:32:38 FileSystemWatcherTests.FileSystemWatcher_EnableRaisingEvents [FAIL]
19:32:38 System.IO.IOException : The configured user limit (128) on the number of inotify instances has been reached.
19:32:38 Stack Trace:
19:32:38 at System.IO.FileSystemWatcher.StartRaisingEvents()
19:32:38 at FileSystemWatcherTests.FileSystemWatcher_EnableRaisingEvents()
19:32:38 Finished: System.IO.FileSystem.Watcher.Tests