Add more content on how to use Exec function

[danvergara]

What does this PR do?

I'm adding more content to command section on the documentation. I didn't know about the Exec method until I came across this issue. So, I thought it'd be nice to have this documented.

Why is it important?

As I described above, that method is really useful when it comes to run tests on a CI environment and everybody should know about it.

Related issues

There's no issue, I just asked if this is important enough to take the time to push some changes to the docs.

Just run mkdocs serve as stated in the contributions guideline.

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[mdelapenya]

Instead of pasting here code snippets, we usually embed code blocks with the <!--codeinclude--> block.

Please take a look at how it's implemented, as it's unfortunately not documented (yet).

It basically needs:

1. in the markdown:

<!--codeinclude-->
[Tab text](../path/to/file.extension) inside_block:name_of_the_block
<!--/codeinclude-->

2. in the file.extension

// name_of_the_block {
... code snippet to be rendered in the markdown
// }

I'm going to use this comment as seed for an issue to include that in our docs.

[danvergara]

Thanks @mdelapenya. That makes sense. The thing is that the examples included in this PR are made up, don't correspond with any test available. I've seen that the those codeinclude chunks reference code in test suite. Want me to include the examples to the test suite? Or where should I put those examples?

[danvergara]

I'm gonna be proactive and I'll add that example to the test suite. I'll let you know when that's ready.

[mdelapenya]

Thanks @danvergara, much appreciated! 🙏

[mdelapenya]

LGTM! Thanks @danvergara for taking the time for submitting this PR. Docs are really important for the onboarding on the project.