Fix docker networking with MAC OS at kogito-examples

Replace host.docker.internal by kubernetes.docker.internal in docker-compose scripts and the associated instructions, to allow visibility between containers in MAC Operative system.

We can keep (as a Note, comment,..) the old host.docker.internal to provide more options in that configuration even it is not always available after Docker Desktop installation in MAC.

https://github.com/kiegroup/kogito-examples/pull/946/files#issuecomment-951792733

"it seems that with default settings you get the kubernetes.docker.internal only. Sadly I was not able to find any official statement about host.docker.internal deprecation so there is a chance this is not permanent though"