do not depend on deprecated nose

Author: pgajdos

tests/test_application.py

@@ -8,7 +8,7 @@
 import logging
 from unittest import TestCase
 
-import nose.tools as nt
+import pytest
 from traitlets.tests.utils import check_help_all_output, check_help_output
 
 from jupyter_contrib_core.application import main as main_app
@@ -59,5 +59,5 @@ def test_00_help_output(self):
         check_help_output(app_module, [])
         check_help_all_output(app_module, [])
         # sys.exit should be called if no argv specified
-        with nt.assert_raises(SystemExit):
+        with pytest.raises(SystemExit):
             main_app([])