Revise Playwright description in README

Updated the description of Playwright to clarify its purpose and supported languages.

Author: mxschmitt

README.md

@@ -2,7 +2,7 @@
 
 > A curated list of awesome tools, utils and projects using Playwright
 
-[Playwright](https://github.com/microsoft/playwright) is a Node.js library to automate Firefox, WebKit and Chromium based browsers via a single API.
+[Playwright](https://github.com/microsoft/playwright) is a framework for Web Testing and Automation. It allows testing Chromium, Firefox and WebKit with a single API. Available for Node.js, Python, .NET and Java.
 
 ## Contents