Add pipelineConfig() parameters for each when property

[orviz]

The arguments that can be passed to JePL's pipelineConfig() method (e.g. configFile, baseRepository, ..) shall be added as new properties for the each when object defined. This change implies that:

• when will act as the Jenkinsfile stage definition
• One could set beforehand the name of the JePL config.yml file, otherwise the behaviour will be the same as now (i.e. random name being generated)
• The jenkinsfile_data object defined in openapi/components/schemas/JePL_jenkinsfile is no longer needed