Replace superlinter with smaller linters

[Alex-deVis]

Prerequisite Checklist

• Read the contribution guidelines regarding submitting new changes to the project;
• Tested your changes against relevant architectures and platforms;
• Updated relevant documentation (if needed).

Description of changes

Superlinter is currently the biggest bottleneck in merging contributions. This is because of its lengthy output and the cumbersome setup required to run it locally.
In reality, we only need linters for C/C++, markdown, python, and bash and a way to run them locally in under 5 minutes.

Note: This PR seems lengthy because it adds the unchanged custom markdown rules from OEH actions.

[teodutu]

I don't like this. We also have Python scripts and a few Go and Java programs. We use one solution to rule them all. Moreover, we already use some global existing configs from this repo [1] which is one of the few things we've done well with this repo's layout. Your PR duplicates a good portion of those.

The bottleneck isn't the super-linter; it's the students' lack of experience using CI/CDs and actually looking at what's failing. Otherwise, you can easily search for the errors shown at the end by super-linter in that massive output and find their source relatively easily.

@razvand what do you think?

[1] https://github.com/open-education-hub/actions/tree/main/super-linter

[Alex-deVis]

We also have Python scripts and a few Go and Java programs.

black is a python linter and is the one used by superlinter as the others were manually disabled. Nobody took the time to configure Go and Java linters so it would be not much extra work to add those.

Moreover, we already use some global existing configs from this repo [1]

Which hides the configuration for linters and provides no way of running it locally. Using a single linter provides no benefit besides writing less in actions.yaml.

it's the students' lack of experience using CI/CDs

I'd also be intimidated if you'd hit me with 8k lines of logs even if nothing failed.