docs: add note about $CI_SERVER_FQDN variable in GitLab CI/CD pipeline

[samuele-ruffino96]

User description

This update adds a note to clarify the availability of the $CI_SERVER_FQDN variable, which was introduced in GitLab 16.10 (docs). Older GitLab versions may not have this variable, which could lead to potential configuration issues.

The change:

• Provides context for users about the $CI_SERVER_FQDN variable, helping to prevent confusion and troubleshooting delays for those on earlier GitLab versions.
• Adds guidance on how to achieve the same result on older versions by using $CI_SERVER_HOST and $CI_SERVER_PORT instead.

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PR Type

Documentation

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Description

• Added documentation note about the $CI_SERVER_FQDN variable, specifying its availability from GitLab version 16.10.
• Provided alternative configuration guidance for users on older GitLab versions using $CI_SERVER_HOST and $CI_SERVER_PORT.
• Aimed to prevent configuration issues and confusion for users on earlier GitLab versions.

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Changes walkthrough 📝

	Relevant files
Documentation	gitlab.md Add note on `$CI_SERVER_FQDN` variable in GitLab docs        docs/docs/installation/gitlab.md Added a note about the $CI_SERVER_FQDN variable availability. Clarified its introduction in GitLab version 16.10. Provided guidance for older GitLab versions using $CI_SERVER_HOST and $CI_SERVER_PORT. +1/-0

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[qodo-merge-pro]

PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

⏱️ Estimated effort to review: 1 🔵⚪⚪⚪⚪

🏅 Score: 95

🧪 No relevant tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Documentation Clarity Consider adding an example of how to combine CI_SERVER_HOST and CI_SERVER_PORT variables for older GitLab versions

[qodo-merge-pro]

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[mrT23]

thanks, docs improvements are always welcomed 👍