Move build to build nodes (label: buildMachine) (#1158)

* Move build to build nodes

* Avoid overwritting test workspaces.

* [BUILD] Experiment with marking stages as skipped

* Fix the settings

* Still skipping

* contd....

* Experimenting

* Refactore invocation of stages

* Fix typo

* Fix typo

* Improve api

* Simplify API #2