Drupal 8 Backup-Migrate running into out-of-memory Error? A large key_value_expire table may be the cause!

On a customer page we were running into problems with backup_migrate aborting with out of memory errors. In contrast to other similar websites we found out that a bug ([#2931611]) in the honeypot module caused the key_value_expire database table to grow up to 2,3 GB of (useless) data.
This bug in detail is being targeted in this issue: [#2997609]