Add ability to test a new nodegenerator tool for Salt model testing

New nodegenerator tool testing step is added as part of Salt model testing
workflow. This step will be only executed on master branches and only for
test-cookiecutter-reclass-chunk job, to do not affect all other jobs.
Also added step will be non-voting and will not affect current flow.

Change-Id: Ibeb431274b14097531df9931937cf07b95c77f47
Related-Prod: PROD-26064 (PROD:26064)
1 file changed