* Update free-courses-ml.md
* Expand title of `bash/shell` section and fix its fragment id to get right cross linking.
* Move `Bootstrap` as subsection of `HTML/CSS` (like in other listings)
* Move `Bootstrap` as subsection of `HTML/CSS` (like in other listings)
* Escape pipes on Markdown
See #5176 for a reason
* Fix `node.js` title like in other listings and alphabetize Node-React sections
* Update free-courses-ml.md
* Fix TOC entry fragment of `HTML / CSS`
Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>