serverless-workflow-hello-world example is referencing adoc in README.md

[Lubo Terifaj]

Describe the bug

serverless-workflow-hello-world example is referencing adoc in README.md

The variables are not resolved properly in the documentation. For example:

• As a developer, you can use {product_name}
• {java_min_version}
• {maven_min_version}
• {quarkus_cli_url}
• Knative Workflow CLI {kn_cli_version}
• {product_name}
• etc.

In addition, there are references to https://github.com/kiegroup/kogito-docs instead of https://github.com/apache/incubator-kie-kogito-docs

Expected behavior

The example either contains a guide how to use the example, or it is referencing well formatted document.

Actual behavior

The referenced adoc document is not suited for final reading document. As a result, a user will end up with unresolved variables.