Fix run_tests to not mask bash8 errors

The addition of the crazy-refs check masked the bash8 exit code.  So add
the same pass/fail handling from exercise.sh to provide a neat summary at
the end of the run.

Change-Id: I169eb90c619a114cf8584bee70b7dcda67769dc5
Merge branch 'conf-functions' into dt-test
Merge branch 'test-service-functions' into dt-test
Merge branch 'update-usb-tools' into dt-test