New place holder in nomad job template to pass docker image name with tasks using docker driver

[deekshith-silabs]

What feature do you want to see added?

In some of the scenarios the job template is same and I need to change only the docker image, for that I need to create new job template.
OR
Some of the developers are working on multiple features where they want to test their docker image changes with their code. In this case we need to be more flexible to launch the nomad jenkins agent based on the docker image we created.

Upstream changes

No response

[deekshith-silabs]

@j3t did you guys get a chance to look into this issues?

[j3t]

Sure, but I don't think it will be implemented. We had a similar discussion with the dynamic template proposal (see #106 (comment))