Issue #3414396: Drush 12 compatibility
I didn't:
- moved
private_message.commands
declaration fromdrush.services.yml
toprivate_message.services.yml
- deleted
drush.services.yml
It is still working with Drush 11 as it is. Drush 12 is able to auto-detect the command since it is now located in the correct directory.
When we will want to drop Drush 11 support, we just will have to delete drush.services.yml