Add/review crs for pacis data

Add (or review for accuracy if it already exists) crs information to pacis datasets, which likely have the same crs (but please check this):

• s3://mdmf/gdp/pacis_guam.zarr
• s3://mdmf/gdp/pacis_kauai.zarr
• s3://mdmf/gdp/pacis_oahu.zarr
• s3://mdmf/gdp/pacis_samoa.zarr

They have the following THREDDS catalog entries, if that is helpful to have:

• https://cida.usgs.gov/thredds/catalog.html?dataset=cida.usgs.gov/guam
• https://cida.usgs.gov/thredds/catalog.html?dataset=cida.usgs.gov/kauai
• https://cida.usgs.gov/thredds/catalog.html?dataset=cida.usgs.gov/oahu
• https://cida.usgs.gov/thredds/catalog.html?dataset=cida.usgs.gov/samoa