Fix/gfs

[zebengberg]

Closes #253

Features

• Add cache_download parameter to the GFSForecast interface. When set to True, downloaded grib data is cached locally. This is consistent with the behavior of the ERA5ModelLevel and HRESModelLevel interfaces.

Fixes

• Update GFS variable names "uswrf" -> "suswrf" and "ulwrf" -> "sulwrf". This accommodates a breaking change introduced in eccodes 2.38.

Tests

• QC test passes locally (make test)
• CI tests pass

Reviewer

Select @ reviewer

[mlshapiro]

I don't think we need to change variable names.

Can you share how you were able to reproduce the error? I tried to to reproduce and did not see any issues.

[mlshapiro]

Can you also require "eccodes>=2.38" in pyproject.toml so that when users re-install they will get this compatible version?