Re-introduce way to have inline code mark-down

[keunes]

Short description: When using back-ticks to indicate inline code, on our website this turns into a button.

`&`

However, in some cases we do still want a regular code block.

URL: https://deploy-preview-174--antennapod-test.netlify.app/documentation/bugs-first-aid/refresh-download-errors

More info:

antennapod.github.io/assets/css/main.scss

Line 39 in f3a7ea9

/* We don't need code and use it as buttons instead */

[keunes]

Just discovered the <kbd> tag, which may be relevant to existing 'button' highlights.