Create Unit Tests

[Nick-Eagles]

In the most ideal case, unit tests could be executed via GHA (see #61) for each nextflow process, but this might prove difficult due to either time or memory limits. Nextflow doesn't currently seem to support a straightforward method for producing unit tests based on existing processes, so I'll first have to establish some fairly automated method for generating these tests (since they are only useful when code changes), and running them locally on-demand (as opposed to through GHA) should suffice for now.