Submodule pointer updates for spack and CMakeModules, remove legacy mirror from aws-pcluster config

[climbfuji]

Summary

• Submodule pointer update for spack (fix setup-meta-modules)
• Submodule pointer update for CMakeModules (latest update of findNetCDF.cmake)
• Remove legacy mirror from aws-pcluster config (tested on AWS pcluster; mirror no longer exists)

Testing

Tested on AWS parallel cluster and/or macOS

Applications affected

n/a

Systems affected

AWS parallel cluster

Dependencies

n/a

Issue(s) addressed

n/a

Checklist

• This PR addresses one issue/problem/enhancement, or has a very good reason for not doing so.
• These changes have been tested on the affected systems and applications.
• All dependency PRs/issues have been resolved and this PR can be merged.