Remove maintiner-trainee status for Jay Swain

Why is this change being made?

Given the amount of current workload, and how many reviews I have to do daily, I've decided to step away from maintainer-trainee for the moment so I can focus on my mental health as well as my team and individual goals. I hope to revisit this in the future.

Does this MR meet the acceptance criteria?

Conformity

• Added description to this MR explaining the reasons for the proposed change, per say-why-not-just-what