Add gitlab-agent-ci-image to projects and add maintainers

Why is this change being made?

By adding the gitlab-agent-ci-image project with maintainers to the existing data we can leverage that in things like Danger for the review roulette, but most importantly for the renovate bot for automated dependency upgrades.

What is the gitlab-agent-ci-image project?

The gitlab-agent-ci-image project hosts all the necessary source code to build and deploy a container image (think docker image) that can / must be used to build and test the gitlab-agent project in CI (for normal builds, but also FIPS compliant builds).

Author Checklist

• Provided a concise title for this Merge Request (MR)
• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
  • Copy/paste the Slack conversation to document it for later, or upload screenshots. Verify that no confidential data is added, and the content is SAFE
• Assign reviewers for this MR to the correct Directly Responsible Individual/s (DRI)
  • If the DRI for the page/s being updated isn’t immediately clear, then assign it to one of the people listed in the Maintained by section on the page being edited
  • If your manager does not have merge rights, please ask someone to merge it AFTER it has been approved by your manager in #mr-buddies
  • The when to get approval handbook section explains the workflow in more detail
• If the changes affect team members, or warrant an announcement in another way, please consider posting an update in #whats-happening-at-gitlab linking to this MR
  • If this is a change that directly impacts the majority of global team members, it should be a candidate for #company-fyi. Please work with internal communications and check the handbook for examples.

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