How to add copy button to code snippets in Hugo

Add copy button to code snippets in Hugo

- Resources:
- https://digitaldrummerj.me/hugo-add-copy-code-snippet-button/
- https://aaronluna.dev/blog/add-copy-button-to-code-blocks-hugo-chroma/
- https://www.dannyguo.com/blog/how-to-add-copy-to-clipboard-buttons-to-code-blocks-in-hugo/