docs: fix badge (#22)

Author: erikbrinkman

README.md

@@ -1,6 +1,6 @@
 MHTML Stream
 ============
-[![build](https://github.com/erikbrinkman/mhtml-stream/actions/workflows/node.js.yml/badge.svg)](https://github.com/erikbrinkman/mhtml-stream/actions/workflows/node.js.yml)
+[![build](https://github.com/erikbrinkman/mhtml-stream/actions/workflows/build.yml/badge.svg)](https://github.com/erikbrinkman/mhtml-stream/actions/workflows/build.yml)
 [![docs](https://img.shields.io/badge/docs-docs-blue)](https://erikbrinkman.github.io/mhtml-stream/)
 [![npm](https://img.shields.io/npm/v/mhtml-stream)](https://www.npmjs.com/package/mhtml-stream)
 [![license](https://img.shields.io/github/license/erikbrinkman/mhtml-stream)](LICENSE)