Add feature flagged Build.latest.gitlab-ci.yml

What does this MR do?

This adds a Build.latest.gitlab-ci.yml with an updated auto-build-image v1.3.1, as a stepping stone towards updating the "stable" Build.gitlab-ci.yml template. We will use the feature flag

redirect_to_latest_template_jobs_build

for rolling out this change to users on GitLab.com. Once it has been on GitLab.com for a few days, the "stable" template will be updated and the "latest" template, and the feature flag, will be removed.

This is being done out of abundance of caution, as this version of auto-build-image uses docker buildx build to build container images, instead of a plain docker build. We do not expect this to be a breaking change, but to ensure a quick rollback, we are releasing this behind a feature flag.

Related to #337987 (closed)

Manual QA for Build.latest.gitlab-ci.yml

See pipeline https://gitlab.com/hfyngvason/minimal-ruby-app/-/pipelines/351828516, run with

# .gitlab-ci.yml

include:
  - file: lib/gitlab/ci/templates/Jobs/Build.latest.gitlab-ci.yml
    project: gitlab-org/gitlab
    ref: add-latest-build-template-for-safer-buildx-rollout

How to setup and validate locally (strongly suggested)

1. Enable the feature flag

   Feature.enable(:redirect_to_latest_template_jobs_build)

2. Run a pipeline in a project with Auto DevOps enabled, or you can use just the Build template:

   include:
     - template: Build.gitlab-ci.yml

3. Verify that the build job is using auto-build-image:v1.3.1

Does this MR meet the acceptance criteria?

Conformity

• I have included changelog trailers, or none are needed. (Does this MR need a changelog?)
• I have added/updated documentation, or it's not needed. (Is documentation required?)
• I have properly separated EE content from FOSS, or this MR is FOSS only. (Where should EE code go?)
• I have added information for database reviewers in the MR description, or it's not needed. (Does this MR have database related changes?)
• I have self-reviewed this MR per code review guidelines.
• This MR does not harm performance, or I have asked a reviewer to help assess the performance impact. (Merge request performance guidelines)
• I have followed the style guides.
• This change is backwards compatible across updates, or this does not apply.

Availability and Testing

• I have added/updated tests following the Testing Guide, or it's not needed. (Consider all test levels. See the Test Planning Process.)
• I have tested this MR in all supported browsers, or it's not needed.
• I have informed the Infrastructure department of a default or new setting change per definition of done, or it's not needed.