Update Mohamed Hamda from CustomersDot DB reviewer to maintainer.

Manager Justification

It's hard to specify hard requirements for becoming a maintainer, which is why the documentation consists of flexible guidelines. Reviewers are encouraged to think of their eligibility for maintainership in the terms of "I could be ready at any time to be a maintainer as long as it is justified".

• The MRs reviewed (Customers Dot | GitLab) by the candidate consistently make it through maintainer review without significant additionally required changes.
• The MRs authored (Customers Dot | GitLab)by the candidate consistently make it through reviewer and maintainer review without significant required changes.

Mohamed has worked with existing Customers Dot database maintainers to expand his skills to the level needed to provide consistent excellent reviews for the Customers Dot application. Mohamed demonstrates good domain knowledge of the customer's dot application by working towards a backend maintership for the application as well.

Before Merging (Manager Tasks)

• Close any relevant trainee maintainer issues with a comment indicating that this merge request is being created, as (they are no longer required to become a maintainer).
• 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 with Owner access level and @gl-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 🤘 😎 🤘