docs: add jaas666 as a contributor for code (#883)

Adds @jaas666 as a contributor for code.

This was requested by JoshuaKGoldberg [in this
comment](#881 (comment))

---------

Co-authored-by: allcontributors[bot] <46447321+allcontributors[bot]@users.noreply.github.com>

Author: allcontributors[bot]