Draft: Add support to Workload for requesting CI Variables explicitly

What is this MR?

This MR is a combination of the extracted code in !200760 (merged) and !200571 (merged) with one addition to connect those 2 together.

You can test this branch by following the same instructions in !200571 (merged) and also see !200571 (comment 2673998362) for how this feature is meant to work.