Add Jessie Young as backend 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 my work as an author and reviewer is consistent with other maintainers".

• 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.

Demonstrates GitLab values in code review

1. Encourages documentation-first mindset by asking questions when code is not self-explanatory and suggesting that issues are opened for anything that requires further investigation or follow-up (example)
2. Demonstrates a security-first mindset by always evaluating MRs with potential security vulnerabilities in mind (example)
3. Reviews code with an eye toward complete test coverage (example) (example) (example)
4. Differentiates between blocking and non-blocking feedback in order to increase efficiency for the MR author (example)
5. Encourages adherence to documented best practices when possible (example) (example)
6. Pragmatic (rather that dogmatic) about code style / readability feedback (example)
7. Considers overall user experience of code changes being proposed (example)
8. Mindful of sensitive feature rollouts, suggests feature flags and other precautions when applicable (example)
9. Evaluates and comments on potential edge cases (example)
10. Has fun in review comments (example)
11. Thorough in reviews to ensure that all edge cases are covered (example)
12. Assists MR authors in making smaller, more iterative changes so that they are easier to review(example)

Demonstrates expertise in key areas of GitLab codebase

Jessie started at GitLab in July 2022 but has already shown expertise in several areas of the codebase.

She worked to upgrade GitLab to OmniAuth 2. Feedback on this work:

"The OmniAuth 2 upgrade has been stalled for years now, and you delivered this in such a short amount time. This was constantly being flagged in our security scans. I underestimated how much work it would take, but I'm glad you weren't intimated at all and were able to contribute upstream to all the gems." (Slack)

She has collaborated with security on a token leak incident. Feedback on this work:

"Jessie showed exceptional expertise while working with security to evaluate and resolve token leak issues. Her collaborative efforts had a multiplier effect on the team's performance, resulting in fast risk reduction for GitLab.com." (Slack)

She has also taken the lead on a large feature for the Auth team: Custom Roles. This involves a detailed understanding of the GitLab app's existing authorization scheme and a strong focus on iteration as we work to deliver value to our customers early and often.

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. Create an access request for maintainer access to gitlab-org/<project>.
2. Join the backend-maintainers slack group
3. Ask the maintainers in your group to invite you to any maintainer-specific meeting if one exists.
4. Let a maintainer add you to @gitlab-org/maintainers/rails-backend
5. Announce it everywhere
6. Keep reviewing, start merging 🤘 😎 🤘