Remove CCCL::Thrust from GLOBAL_TARGETS.

[bdice]

Description

I saw an error (below) and @robertmaynard helped me identify that this change was needed.

I was building cuGraph (this branch) with rapids-cmake pointing to this branch of cuCollections.

-- CPM: Adding package [email protected] (cccl-2.2.0)
CMake Error at build/release/_deps/rapids-cmake-src/rapids-cmake/cmake/make_global.cmake:59 (set_target_properties):
  Attempt to promote imported target "CCCL::Thrust" to global scope (by
  setting IMPORTED_GLOBAL) which is not built in this directory.
Call Stack (most recent call first):
  build/release/_deps/rapids-cmake-src/rapids-cmake/cpm/find.cmake:189 (rapids_cmake_make_global)
  build/release/_deps/rapids-cmake-src/rapids-cmake/cpm/cccl.cmake:85 (rapids_cpm_find)
  build/release/_deps/cuco-src/cmake/thirdparty/get_cccl.cmake:18 (rapids_cpm_cccl)
  build/release/_deps/cuco-src/cmake/thirdparty/get_cccl.cmake:21 (find_and_configure_cccl)
  build/release/_deps/cuco-src/CMakeLists.txt:79 (include)

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]

/merge