Is your feature request related to a problem? Please describe.
cuDF has not supported nvcomp 2.2.0 for a long time, but rapids-cmake's versions.json still has an entry for nvcomp 2.2.0 and the outdated repo page (the nvcomp repo states, "This page will be retired soon" so the git_url will soon be irrelevant). However, we can't remove this outdated information because the versions.json parser expects git_url and git_tag to exist.

Describe the solution you'd like
Update the parser so that proprietary packages can be used with only proprietary_binary information, without specifying git_url and git_tag.

Describe alternatives you've considered
One alternative would be to allow an empty string like "git_url": "" / "git_tag": "", but that also fails with rapids_cmake can't parse 'nvcomp' json entry, it is missing a `git_url` entry.

Additional context
Related to rapidsai/cudf#16757.