Timeout when attempting to move issues in board column

@kencjohnston reported an issue in Slack where he is seeing timeouts when attempting to move certain issues positions in board columns:

• Board
• Issue

Every time I attempt to adjust the relative position of that issue in the ~KCJ:Ready column (it’s at the bottom now) it errors.

Backtrace is here: https://log.gprd.gitlab.net/app/discover#/doc/7092c4e2-4eb5-46f2-8305-a7da2edad090/pubsub-rails-inf-gprd-007125?id=z9JnLn0BDAy7t_i_ok3G - It times out when querying the left-hand-side neighbor of the issue. (The next issue with lower position)