Add functionality to read rules from a folder

[mehrdad-khojastefar]

Description

The problem I tried to solve was organizing our rules in my workplace, we had so many rules and maintaining them was getting kind of hard.
The solution was somewhat simple, the rules configMap needed to be updated so that it reads from a folder and scans all files with .yaml extension and build the rules configMap from them.
I hope this feature helps you too because now our rules are much more cleaner and maintainable.
Thanks for this awesome project as well.

with this feature all rules can be in its own folder and you just need to pass the folder name to the rootRulesFolder in the values.yaml

Checklist

• [done] I have reviewed the contributing guidelines.
• [no need] I have included unit tests for my changes or additions.
• [done] I have successfully run make test-docker with my changes.
• [done] I have manually tested all relevant modes of the change in this PR.
• [done] I have updated the documentation.
• [done] I have updated the changelog.

Questions or Comments

I am waiting for your comments, if everything is ok then I can write the documentation and etc. for this PR.

[jertel]

Thanks for the submission! I don't see a reason not to include this so please proceed with documentation and changelog updates. Also, I think your PR accidentally included changes to default values, and some formatting changes. Please revert those since they don't appear to be part of your new feature.

[mehrdad-khojastefar]

Thanks for the comment. Really looking forward to contribute more!
I've updated the chart's readme and changelog.
Also I reverted the formatting of values.yaml file.
I've double checked the changes and tested them once more and everything seems ok .