Make @stomlinson a database trainee maintainer

Why is this change being made?

Marking myself as a database trainee maintainer. (#11934 (closed))

Author Checklist

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• Added a description to this MR explaining the reasons for the proposed change, per say-why-not-just-what
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requested review from @craig-gomes

assigned to @stomlinson

added this merge request to the merge train at position 2

merged

mentioned in commit 2e54e81e