Fix duplicated test_dendrogram_orientation test.

Author: theengineear

plotly/tests/test_optional/test_opt_tracefactory.py

@@ -447,7 +447,7 @@ def test_dendrogram_orientation(self):
         tickvals_top = np.array(dendro_top['layout']['xaxis']['tickvals'])
         self.assertTrue((tickvals_top <= 0).all())
 
-    def test_dendrogram_orientation(self):
+    def test_dendrogram_orientation_two(self):
         X = np.array([[1, 2, 3, 4],
                       [1, 1, 3, 4],
                       [1, 2, 1, 4],