added AVL search algorithm in searching techniques#1375

ajay-dhangar merged 2 commits intocodeharborhub:maincodeharborhub/codeharborhub.github.io:mainfrom

Maheshwari-Love:add/avl-treeMaheshwari-Love/codeharborhub.github.io:add/avl-treeCopy head branch name to clipboard