Remove incorrect docs link shown for push rule file size limit

What does this MR do and why?

Related_to: Fix the push rule file limit size error (#535865 - closed)

Previously, the error message shown when a push was rejected due to a project-level push rule (max file size) included links to documentation about GitLab.com's free-tier push limits. This was misleading, as those links apply to global SaaS plan limits, not to custom push rules.

This MR ensures that when the file size limit is enforced via a project's push rule, we no longer show those unrelated documentation links in the error message.

Screenshots or screen recordings

global limit error message	push rule limit error message

How to set up and validate locally

1.Set a push rule file size limit in the project settings. (settings -> Repository -> Push rules)

2.Try pushing a file larger than the limit – it should be rejected.

3.Try pushing a file within the limit – it should succeed.

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