Add instructions for vulnerablecode integration

[TG1999]

No description provided.

[tdruez]

@TG1999 Could you add an introduction paragraph about the context of this integration.
You added the "how" but we also need the "why".

Also, a section about the usage of the find_vulnerabilities pipeline would be useful, following the configuration parts.

[TG1999]

@tdruez done!

[tdruez]

It would be more interesting to display screenshots about the actual vulnerability results of running the pipeline instead of showing how to add and run a pipeline, which is already cover in other tutorial.

For example:

and so on.

[TG1999]

@tdruez done!