PoC to fix wrong port assignment of links

What does this MR do?

The links generated by entities can have a wrong port assignment if the Rails application is running behind a reverse proxy. The reason is since the application is running behind a reverse proxy, generating URLs without the request context sets the default port to the URLs generated which is incorrect.

In my case, I am running a local Nginx process which listens on port 80 and 443 and I have the entry in my /etc/hosts file to resolve the gitlab.localhost to the IP address in my LAN but the URLs generated by Rails application is always pointing to gitlab.localhost:3000 as it does not generate the URLs within the context of the request. I think we should inject the controller context to entities to fix this behavior.

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
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Availability and Testing

• [-] Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

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• [-] Label as security and @ mention @gitlab-com/gl-security/appsec
• [-] The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
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