Remove a sleep no longer needed with the current base zmq version

IPython/html/notebookapp.py

@@ -714,8 +714,6 b' class NotebookApp(BaseIPythonApplication):'
         
         This doesn't work on Windows.
         """
-        # FIXME: remove this delay when pyzmq dependency is >= 2.1.11
-        time.sleep(0.1)
         info = self.log.info
         info('interrupted')
         print(self.notebook_info())