* Improving the coding standard for AvLTree Data Structure
* Test case creation for AVLTree
~ Created test cases for AVL Tree
~ Indentation fix for AVLTree.js
* Auto-update DIRECTORY.md
* Change in logic for data list
* Style fix based on standard.js
Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
