Synchronize met and metplus packages with upstream

[climbfuji]

Description

The package recipe for met differs significantly between our fork and the upstream/authoritative codebase, with ours being the correct version.

I created pull request spack/spack-packages#2992 to update the MET package upstream from spack-stack-dev. Once that PR is merged (with style fixes and addressing of reviewer comments), we need to update our version from upstream.

At the same time, we should pull metplus from upstream; there is only one difference, and that is an explicit version constraint on netcdf-c for certain versions of metplus.