Cannot restore backup in docker container

I have the problem that I can’t restore my backup. I have created the backup with the help of this documentation: https://gitlab.com/help/raketasks/backup_restore.md

I get following message, when I try to restore my backup:

docker exec -it gitlab gitlab-rake gitlab:backup:restore
Unpacking backup ... done
2019-09-17 18:17:11 +0000 -- Restoring repositories ...
2019-09-17 18:17:11 +0000 -- done
2019-09-17 18:17:11 +0000 -- Restoring uploads ... 
2019-09-17 18:17:12 +0000 -- done
2019-09-17 18:17:12 +0000 -- Restoring pages ... 
2019-09-17 18:17:12 +0000 -- done
2019-09-17 18:17:12 +0000 -- Restoring lfs objects ... 
2019-09-17 18:17:12 +0000 -- done
This task will now rebuild the authorized_keys file.
You will lose any data stored in the authorized_keys file.
Do you want to continue (yes/no)? yes

Deleting tmp directories ... done
done
done
done
done
Warning: Your gitlab.rb and gitlab-secrets.json files contain sensitive data 
and are not included in this backup. You will need to restore these files manually.
Restore task is done.

After Restore task is done. the restore process is killed.

The thing is, that I had a backup of the gitlab.rb and gitlab-secrets.json files restored.

I want to restore the backup on a complete fresh installation of GitLab-CE (docker-image) on my local machine with a complete new PostgreSQL instance.

The configuration for Gitlab is set in the docker command with --env GITLAB_OMNIBUS_CONFIG=.