ci: migrate open source licensing pipeline to a different Concourse URL

[LukeWinikates]

question: Can we also create a new private repo for these internal concourse pipelines, and store them there instead?

[suprajanarasimhan]

Thanks for all of the feedback, @LukeWinikates! I'll look at this later today.

[LukeWinikates]

for reference, here's what the java/python SDKs' osspi pipelines look like