Bump gitlab-omnibus-builder version to 5.57.2

What does this MR do and why?

Bumps the BUILDER_IMAGE_REVISION variable to 5.57.2 in gitlab-ci-config/variables.yml, updating the gitlab-omnibus-builder image version used for CI builds.

5.57.2 is a minimal, targeted patch of 5.57.1 (the version currently pinned on 19-0-stable) that only backports the golang-fips hkdf-expandlabel-read fix, avoiding unrelated changes merged into gitlab-omnibus-builder master since 5.57.1: gitlab-omnibus-builder!494 (merged)

New version fixes issue with patched FIPS Golang ( see Skip golang-fips hkdf-expandlabel-read patch in... (gitlab-omnibus-builder!491 - merged) )

Note: This MR cannot be merged until gitlab-omnibus-builder MR !494 (merged) is merged and tag 5.57.2 is cut and its image published.

Related issues

• https://gitlab.com/gitlab-com/gl-infra/gitlab-dedicated/team/-/work_items/13088+

MR acceptance checklist

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

• This MR is backporting a bug fix, documentation update, or spec fix, previously merged in the default branch.
• The original MR has been deployed to GitLab.com (not applicable for documentation or spec changes).
• This MR has a severity label assigned (if applicable).

Note to the merge request author and maintainer

If you have questions about the patch release process, please:

• Refer to the patch release runbook for engineers and maintainers for guidance.
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