Unhelpful error message for ClimaArtifact

[Sbozzolo]

Suppose an artifact is undownloadable (too big). The error message when the file is not available would look like

ERROR: LoadError: Artifact "era5_land_forcing_data2021" was not found by looking in the paths:
  ~/.julia/artifacts/ec424296df6b60cfe273ac8f981701fbbed0bd8a
  ~/.julia/juliaup/julia-1.10.4+0.x64.linux.gnu/local/share/julia/artifacts/ec424296df6b60cfe273ac8f981701fbbed0bd8a
  ~/.julia/juliaup/julia-1.10.4+0.x64.linux.gnu/share/julia/artifacts/ec424296df6b60cfe273ac8f981701fbbed0bd8a
Try `using Pkg; Pkg.instantiate()` to re-install all missing resources if the artifact is part of a package or call `Pkg.ensure_artifact_installed` (https://pkgdocs.julialang.org/v1/api/#Pkg.Artifacts.ensure_artifact_installed) if not.
...

This doesn't tell the user that it is their responsability to download that file.