docs: update link to npmjs package

Signed-off-by: Marvin <7430964+marpme@users.noreply.github.com>

Author: marpme

README.md

@@ -4,10 +4,9 @@
 <em>Simplifying the struggle of mocking and reimplementing NextAPIRequests and NextAPIResponses
 in order to test and validate NextJS serverless functions.</em>
 
-
-![npm (tag)](https://img.shields.io/npm/v/@next-testing/api/latest)
-![NPM](https://img.shields.io/npm/l/@next-testing/api)
-![npm](https://img.shields.io/npm/dt/@next-testing/api)
+[![npm (tag)](https://img.shields.io/npm/v/@next-testing/api/latest)](https://www.npmjs.com/package/@next-testing/api)
+[![NPM](https://img.shields.io/npm/l/@next-testing/api)](https://www.npmjs.com/package/@next-testing/api)
+[![npm](https://img.shields.io/npm/dt/@next-testing/api)](https://www.npmjs.com/package/@next-testing/api)
 
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