DASSH installation/execution scripts using Workbench Conda virtual environment

This installation/execution setup is currently passing on my local machine. I can run it from the command line and from the Workbench GUI.

One potential hangup - execution in the GUI does not print messages to the screen as the model is running. Potentially something to consider. I think this could be because DASSH is running in an environment within the Workbench Python environment rather than the Workbench environment directly. The messages are printed to the screen at the end of the calculation, though. Let's discuss.

Also: the build is failing the pipeline tests, which don't seem to be failing elsewhere. Looks like an ImportError during setup regarding a module called "pathlib" - can you advise, @nstauff or @pshriwise?