Create a Jenkins X test pipeline for the platform staging team

To validate  our Jenkins X environment, currently, we're relying on the platform-staging Jenkins X team (K8s namespace).
This team relies on:

• A custom Jenkins X image, similar to the one used for the platform team.
• A custom environment, similar to the one used for the platform team.
• Some imported GitHub repositories.

To validate a change, we mainly run the nuxeo job, considering that if it passes it means the environment is OK.

Most of the time, we only need to validate a Jenkins upgrade, a new Jenkins plugin or a plugin upgrade.

Yet, running the whole nuxeo pipeline can be:

• resource-consuming
• time-consuming to have a status

Instead (or in addition), we could have a test pipeline to validate a maximum number of typical stages that we are running in our pipelines, for instance:

• mvn xxx
• skaffold xxx # build and push an image to the internal registry/public registry
• (jx step) helm install xxx
• jx xxx
• kubectl xxx
• sh xxx
• perl xxx