Check that direct connectables produce the same results as images

[Julian]

We now have multiple possible ways of speaking to a single implementation -- e.g. direct:python-jsonschema and image:python-jsonschema.

Users will expect these to be equivalent with regard to compliance.

It would be nice to have a workflow which checks this -- by running both connectables and asserting that the results are the same.

Note that of course there is some possibility that:

1. an implementation has some nondeterministic behavior
2. the version connected to directly is different than that of the image

but we should likely accept these and still have something which will notify us if behavior begins to drift here.