Fixed typo in testing-contracts.md

src/pages/write-smart-contracts/testing-contracts.md

@@ -7,7 +7,7 @@ duration: 15 minutes
 
 ## Introduction
 
-Clarity, the smart contracting language, is based on [LISP](<https://en.wikipedia.org/wiki/Lisp_(programming_language)>). Clarity is an interpreted language, and [decidable](https://en.wikipedia.org/wiki/Recursive_language). In this tutorial, you will learn how to test Clarity and how use [Mocha](https://mochajs.org/) to test Clarity contracts while you develop them.
+Clarity, the smart contracting language, is based on [LISP](<https://en.wikipedia.org/wiki/Lisp_(programming_language)>). Clarity is an interpreted language, and [decidable](https://en.wikipedia.org/wiki/Recursive_language). In this tutorial, you will learn how to test Clarity and how to use [Mocha](https://mochajs.org/) to test Clarity contracts while you develop them.
 
 - Have a working Clarity starter project
 - Understand how to test Clarity code using `.ts` files and Mocha.