Reset Ghost migration lock on Heroku

Problem:

ERROR Migration lock was never released or currently a migration is running.

If you are sure no migration is running, check your data and if your database is in a broken state, you could run `knex-migrator rollback`.

Answer ‒ on your production database, call:

UPDATE migrations_lock set locked=0 where lock_key='km01';

I've been using DBeaver for the second step and it's very convenient. Thanks to dan1410 for recommending DBeaver to me!