Resolve "cprep Conversion to Zarr"

Closes #56.

This workflow converts CPREP files in Netcdf format living on Opendap urls to zarr files living at 's3://nhgf-development/workspace/DataConversion/gdp/cprep'. The workflow includes a routine to create STAC items from the converted zarr files, but currently writes those json files to a local folder. The output path may be changed later to create the actual STAC items.