jenkins jobs update

* add proper yaml multiline in jjb yaml jobs definition
* add collect artifacts if job fails into jjb job definition macros
* remove prepare_incubator_at function and its call from dashboard test job
* add sh -xe to the documentation build job launch

Change-Id: I4c07d4c55ee8833449b03294749710c3b9b568dc
Closes-Bug: 1340140