Disallow nvcomp git checkout

[bdice]

Description

Closes #702.

This adopts a minimal approach that does not affect parsing logic, it only disables git checkout of the nvcomp dependency.

Checklist

• I am familiar with the Contributing Guidelines.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.
• The cmake-format.json is up to date with these changes.
• I have added new files under rapids-cmake/
  • I have added include guards (include_guard(GLOBAL))
  • I have added the associated docs/ rst file and update the api.rst

[bdice]

I am marking this as non-breaking because the nvcomp 2.2.0 git checkout has been unsupported for a while.

[KyleFromNVIDIA]

You'll need to update the tests in CI to account for the fact that Git is no longer supported.

You may even consider throwing an error if PROPRIETARY_BINARY is not passed.

[bdice]

@KyleFromNVIDIA If you have bandwidth, I would appreciate help with this. Otherwise I will come back to it later.