Add line ending to last line of file

Author: jasongrout

jupyter_core/tests/test_command.py

@@ -224,4 +224,4 @@ def test_argv0(tmpdir):
     out = check_output([sys.executable, str(jupyter), 'witness'], env=env)
 
     # Make sure the first argv is the full path to the executing script
-    assert f'{jupyter}-witness'.encode() in out
+    assert f'{jupyter}-witness'.encode() in out