Improve DevOps documentation section and formatting (#1988)

[VibhuGupta-dev]

This pull request adds the missing DevOps make commands documentation that was not previously included on the /reference-guide/cookieplone-make-commands.html page.

The DevOps-related Make commands exist in the project structure, but their documentation was never referenced or explained. This update introduces a properly structured section describing those commands, ensuring users can understand and use the DevOps tools provided by Cookieplone.

This improves the completeness of the reference guide and resolves the documentation gap reported in Issue #1988.

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📚 Documentation preview 📚: https://plone6--1991.org.readthedocs.build/

[stevepiercy]

@VibhuGupta-dev with every PR, because you haven't signed the PCA, you must include the statement granting permission to publish.

Follow Contribute to documentation and Granting permission to publish. I can't merge this without your permission to publish in either of the two acceptable forms

[VibhuGupta-dev]

@VibhuGupta-dev with every PR, because you haven't signed the PCA, you must include the statement granting permission to publish.

Follow Contribute to documentation and Granting permission to publish. I can't merge this without your permission to publish in either of the two acceptable forms

I, Vibhu Gupta , agree to have this contribution published under Creative Commons 4.0 International License (CC BY 4.0), with attribution to the Plone Foundation.

[stevepiercy]

@VibhuGupta-dev I'm sorry, but you did not include any of my suggestions from my review in your original pull request at #1989. Please do so. Better yet, just reopen that PR and commit the suggestions through the GitHub UI instead of your IDE.