Ensure npm dev dependencies are available after mtaBuild as they are required by certain tests.
Co-authored-by: Kevin Hudemann <kevin.hudemann@sap.com>
Co-authored-by: Daniel Kurzynski <daniel.kurzynski@sap.com>
Extend mta build step to install maven artefacts after build to allow re-using them in later stages (additional unit or integration tests which might not be running as part of the "build" life-cycle).
