Fixes #4404

- add javadoc deprecated tag w/ reason

To support Spring Boot 3.0 the local deployer needs the ability to find an open port.

This is because SocketUtils was removed from the Spring Framework.

Resolves #213

   The way that Task (And Task Launcher) handle and use env. variables brings hight risk to expose
   sensitive information. Therefore it is safer not to list variables's values in any log level.

- Bring back removed use of env inherit/retain options
- Fixes #205

- Fix checkstyle warnings
- Enable checkstyle on default

- Migrate to assertj
- Fixes #204