Update to the latest stack versions and bugfixes
Release notes:
- Bugfix for issue #75
- Change Spring boot to version
2.4.0-M1. - Change Spring Cloud to version
2020.0.0-M3. - Update RabbitMQ to the latest
3.x.xversion.
2.4.0-M1.2020.0.0-M3.3.x.x version.