Add Andy as a database maintainer

Manager Justification

• The MRs reviewed by the candidate consistently make it through maintainer review without significant additionally required changes.
• The MRs authored by the candidate consistently make it through reviewer and maintainer review without significant required changes.

@Andysoiron joined GitLab more than 3 years ago. He is a GitLab backend maintainer, but he wanted to learn more about databases. @sabrams was helping him during his journey as a trainee maintainer mentor.

• He has authored more than 200 merge requests, 28 database merge requests.
• He has reviewed and approved more than 465 merge requests, 110 database merge requests.
• He has an active trainee maintainer issue.

Before Merging (Manager Tasks)

• Mention the maintainers from the given specialty and ask them to provide feedback to the manager directly.
• Leave this merge request open for 1 week, to give the maintainers time to provide feedback.
• Ensure we have at least 2 approvals from existing maintainers.

Once This MR is Merged

1. Ask a maintainer to add you to @gitlab-org/maintainers/database
2. Join the database_maintainers slack group
3. Ask the maintainers in your group to invite you to any maintainer-specific meeting if one exists.
4. Announce it everywhere
5. Keep reviewing, start merging 🤘 😎 🤘