Update 4_Neural_Style_Transfer_with_Eager_Execution.ipynb (#7152)

Small spelling fix: Common -> Commons

research/nst_blogpost/4_Neural_Style_Transfer_with_Eager_Execution.ipynb

@@ -58,7 +58,7 @@
         "<img src=\"https://github.com/tensorflow/models/blob/master/research/nst_blogpost/The_Great_Wave_off_Kanagawa.jpg?raw=1\" alt=\"Drawing\" style=\"width: 200px;\"/>\n",
         "\n",
         "[Image of Green Sea Turtle](https://commons.wikimedia.org/wiki/File:Green_Sea_Turtle_grazing_seagrass.jpg)\n",
-        "-By P.Lindgren [CC BY-SA 3.0  (https://creativecommons.org/licenses/by-sa/3.0)], from Wikimedia Common\n",
+        "-By P.Lindgren [CC BY-SA 3.0  (https://creativecommons.org/licenses/by-sa/3.0)], from Wikimedia Commons\n",
         "\n",
         "\n",
         "Now how would it look like if Hokusai decided to paint the picture of this Turtle exclusively with this style? Something like this?\n",