GITLAB_USER_LOGIN getting wrong value randomly

What does this MR do and why?

This MR aims to resolve an issue where the user that triggered a pipeline is incorrect.

The fix that we're trying is to set the user and the variables on every retry in order to keep the object up to date.

Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

How to set up and validate locally

There are steps on how to reproduce the bug in the issue's description but we haven't been able to actually reproducing so we're trying out this solution based on the bug's behaviour and nature

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #337063 (closed)