Clean up.

setupbase.py

@@ -161,7 +161,8 @@ class CoreDeps(Command):
 
     # Representative files that should exist after a successful core setup
     targets = [
-        pjoin(here, 'jupyterlab', 'schemas', '@jupyterlab', 'shortcuts-extension', 'plugin.json'),
+        pjoin(here, 'jupyterlab', 'schemas', '@jupyterlab',
+            'shortcuts-extension', 'plugin.json'),
         pjoin(here, 'jupyterlab', 'themes', 'jupyterlab-theme-light-extension',
             'images', 'jupyterlab.svg')
     ]