docs(readme): add badges

Author: andreruffert

README.md

@@ -2,6 +2,11 @@
 
 > Syntax Highlighting using the CSS Custom Highlight API.
 
+[![Test status](https://img.shields.io/github/actions/workflow/status/andreruffert/syntax-highlight-element/test.yml?label=Test&logo=github&color=32A9C3&labelColor=1B3C4A)](https://github.com/andreruffert/syntax-highlight-element/actions/workflows/test.yml)
+[![npm version](https://img.shields.io/npm/v/syntax-highlight-element?color=32A9C3&labelColor=1B3C4A)](https://www.npmjs.com/package/syntax-highlight-element)
+[![npm downloads](https://img.shields.io/npm/dm/syntax-highlight-element?logo=npm&color=32A9C3&labelColor=1B3C4A)](https://www.npmjs.com/package/syntax-highlight-element)
+[![GitHub](https://img.shields.io/badge/source-a?logo=github&color=1a1a1a)](https://github.com/andreruffert/syntax-highlight-element)
+
 The code is highlighted without having to wrap a bunch of `<span>` elements around each token, thanks to [Prism][prism_github]'s tokenizer and the [CSS Custom Highlight API][MDN_CSS_Custom_Highlight_API].
 
 <div align="center">