Is your feature request related to a problem? Please describe.

Ultimately I would like to add support for GitHub style rendering of task lists using [ ] and [x] in a downstream repository of executablebooks – e.g. jupyter-book – and I've tracked down this repository as a candidate for a pull request.

Describe the solution you'd like

Porting a plugin for markdown-it such as @hackmd/markdown-it-task-lists, source at revin/markdown-it-task-lists to the extensions folder in this repository.

Describe alternatives you've considered

Creating a separate repository for the plugin and adding configuration options for external plugins to the downstream repositories MyST-Parser, MyST-NB and jupyter-book. This is a bigger task than I can do by myself.

Additional context

Se pull request.