Resolve "Trainee BE maintainer (GitLab) - Alex Pooley"

Why is this change being made?

Added Alex Pooley as trainee maintainer.

@dsatcher Can we please catch up on this issue every 6 weeks or so?

Does this MR meet the acceptance criteria?

Assign to DRI

• Did you assign this change to the correct DRI of the page or information you are changing?

Conformity

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

Closes #6609 (closed)