Add Contribution Guide in kogito-docs

We need a new component in Kogito Serverless Workflow Guides, where the author can see the contribution guidelines and basic Antora recommended practices to write the guide.
For example, document attributes, referencing pages between modules, etc.

Reference Doc for How to write: https://docs.google.com/document/d/1FywIbnWrXBhNjWtFJI6C7W1J8oyoYRH6xxZTS-GOhJM/edit?usp=sharing