update directory of bundle for tests since protected

Author: chriddyp

plotly/tests/test_optional/test_offline/test_offline.py

@@ -23,7 +23,7 @@ def test_no_errors_are_raised_when_initializing_offline_mode(self):
     @raises(PlotlyError)
     def test_initializing_before_downloading_raises_an_error(self):
         try:
-            os.remove(plotly.offline.PLOTLY_OFFLINE_BUNDLE)
+            os.remove(plotly.offline.offline.PLOTLY_OFFLINE_BUNDLE)
         except OSError:
             pass