Remove trailing comma (#1271)

The comma is problematic as reported in pytorch/captum#553

Author: bilalsal

recipes_source/recipes/Captum_Recipe.py

@@ -136,7 +136,7 @@
 attribution_dog = np.transpose(attribution_dog.squeeze().cpu().detach().numpy(), (1,2,0))
 
 vis_types = ["heat_map", "original_image"]
-vis_signs = ["all", "all"], # "positive", "negative", or "all" to show both
+vis_signs = ["all", "all"] # "positive", "negative", or "all" to show both
 # positive attribution indicates that the presence of the area increases the prediction score
 # negative attribution indicates distractor areas whose absence increases the score
 
@@ -186,4 +186,4 @@
 # 
 # Another useful post by Gilbert Tanner:
 # https://gilberttanner.com/blog/interpreting-pytorch-models-with-captum
-# 
+#