Patch series to add to and imporve tests for CoreSight

This improves how perf test handles finding shell scripts to run as part of the testing allowing sub-directories, skipping files that are not intentional shell script tests and then adds a set of tests that improve what we cover for Arm CoreSight testing. The goal of these tests is to expand the scenarios and data traced and examined to track quality of trace data and improvements to that over time.

Eventually it'd be neater to break up the current Arm CoreSight tests into smaller focused tests that share the same infrastructure, but this here would be a first step.