Remove pipeline-specific logic from test scripts
Remove pipeline-specific logic from test scripts

This logic has been moved into the Omnibus Buildkite Plugin.
These scripts can now be used outside of the Buildkite pipelines.

Signed-off-by: Tom Duffield <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@tomduffield.com>

chef/supermarket,chef/supermarket,chef/supermarket,chef/supermarket,chef/supermarket