Added a new resource

Hey, I have added a reference link for Binary Tree in Data Structure under Binary Tree - Definition. I came upon this article while looking for resources to learn Data Structure. This citation, in my opinion, will enhance the content of this article. Hope that my contribution will benefit other learners.

Author: Sachinbhatttech

README.md

@@ -138,6 +138,8 @@ Big-Theta refers to the tight bound of time or space complexity of an algorithm.
 - Is a tree like data structure where every node has at most two children.
   - There is one left and right child node.
 
+For a full binary-tree reference see [Here](https://www.scaler.com/topics/data-structures/binary-tree-in-data-structure/)
+
 #### What you need to know
 - Designed to optimize searching and sorting.
 - A **degenerate tree** is an unbalanced tree, which if entirely one-sided, is essentially a linked list.