Allow JupyterLab to fail gracefully on install for now

setupbase.py

@@ -363,9 +363,7 @@ class JavascriptDependencies(Command):
             run(['npm', 'install', '--progress=false'], cwd=self.lab_dir)
             run(['npm', 'run', 'build'], cwd=self.lab_dir)
         except Exception as e:
-            print("Failed to run `npm install`: %s" % e, file=sys.stderr)
-            print("You can install js dependencies with `npm install`", file=sys.stderr)
-            raise
+            print("Failed to install JupyterLab`: %s" % e, file=sys.stderr)
 
         # update package data in case this created new files
         update_package_data(self.distribution)