Update README.md

Author: LuisHung96

README.md

@@ -268,5 +268,5 @@ For more you can check **[course info](https://www.deeplearning.ai/courses/tenso
     </details>
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-## <b>Referece<b>
+## <b>Reference<b>
 <b>[DeepLearning.AI TensorFlow Developer Professional Certificate](https://www.coursera.org/professional-certificates/tensorflow-in-practice)<b>