Add markdown linter in CI

[MarcoIeni]

It would be nice to have something in CI that tells us if markdown is correct. For example this markdown is not valid:

# section 1

### section 2

Or stuff like: avoid tabs or detect trailing whitespaces.

[simonsan]

We could use this action for linting https://github.com/marketplace/actions/markdownlint-mdl-action

Not sure how complicated it is though to find a "style" that fits but at least tabs, whitespaces and the section headers should be easily setup.

[MarcoIeni]

Other ones I've found:

• https://github.com/logansquirel/action-markdownlint (no)
• https://github.com/ruzickap/action-my-markdown-linter (no)
• https://github.com/avto-dev/markdown-lint (uses https://github.com/DavidAnson/markdownlint )

[MarcoIeni]

We have to choose between:

• The action simonsan suggested - uses https://github.com/markdownlint/markdownlint
• https://github.com/avto-dev/markdown-lint - uses https://github.com/DavidAnson/markdownlint

Thanks to the parameter "number of stars" the second option is winning at the moment :joy: Do you have any preference?

[simonsan]

* https://github.com/avto-dev/markdown-lint - uses https://github.com/DavidAnson/markdownlint

Seems better maintained and has the better documentation and tooling (e.g. VScodium extension) it seems

[MarcoIeni]

Nice, let's use that one. Who wants to start working on this can leave a comment here.

[Takashiidobe]

I'd like to work on this:

I propose doing a few things:

• Running markdownlint on all markdown files in the project:
• Then setting up the the github action to check for markdown lint errors on PR.

[simonsan]

I'd like to work on this:

I propose doing a few things:

* Running markdownlint on all markdown files in the project:

* Then setting up the the github action to check for markdown lint errors on PR.

Nice!