docs: Example - Integrating Crowdsec

[mivek]

Description

I added a page explaining how to use crowdsec with docker-mailserver.
The page is not a complete tutorial on how to install and configure crowdsec but covers the docker-mailserver logs parsing by crowdsec.

I added the page under examples/tutorials

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation (README.md or the documentation under docs/)

[polarathene]

Thanks for the contribution!

I also really like how you've leveraged the admonition types and respected out link conventions ❤️

Some typos to address and minor revisions, but otherwise great work! 😎

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We are looking at bringing Vector into DMS at some point to improve our logging support. You may want to subscribe to that issue in the event your guide here needs to be adjusted.

[mivek]

Thank you @polarathene for you feedback, I applied the suggested changes.

I will squash the commits when the PR is approved.

[polarathene]

LGTM 👍

@georglauterbach do you want to squeeze this into the v13 release or defer to v13.1?

[github-actions]

Documentation preview for this PR is ready! 🎉

Built with commit: 999bf37

[georglauterbach]

Squashing this and #3654 into v13.0.0 no problem 🚀

[williamdes]

You might be interested in https://github.com/datacenters-network/mails/tree/main/crowdsec/parsers