Add experimental-tripleo checks for tripleo deps.

These are projects we'll want symmetric gating on eventually, and a
new pipeline allows us to work up tests and make sure things are
working properly in advance of having a sufficiently high uptime cloud
with fast enough tests to be in the main experimental queue.

Change-Id: Ic6369910ba162648608e17ec2c4057dc982120f5
Merge "Add experimental-tripleo checks for tripleo deps."