There were some concerns with the custom filter migration script dropping a table,
thus making it unsafe to run in a zero-downtime setting. Upstream introduced
a way to run migrations after deployment, so revisit the old migration script to
make use of this.
Adopted from GitLab CE. Generate new migration with:
rails g post_deployment_migration name_of_migration_here
By default they are run together with db:migrate. To not run them,
the env variable SKIP_POST_DEPLOYMENT_MIGRATIONS must be set
Code by Yorick Peterse <yorickpeterse@gmail.com>, see also:
83c8241160