Update to use rapids-export(COMPONENTS) feature. (#12959)

Not only does this simplify the `cudf` CMakeLists.txt it removes a bug where we failed to install the testing dependencies file since it relied on internal rapids-cmake details.

Expected to fix the following:

- cuspatial issues with not finding GTest targets
- [spark-rapids-jni](https://github.com/NVIDIA/spark-rapids-jni) issues with not finding GTest targets

Fixes #12976

Authors:
  - Robert Maynard (https://github.com/robertmaynard)
  - Vyas Ramasubramani (https://github.com/vyasr)

Approvers:
  - Bradley Dice (https://github.com/bdice)
  - Mike Wilson (https://github.com/hyperbolic2346)
  - Jason Lowe (https://github.com/jlowe)

URL: #12959

cpp/CMakeLists.txt

@@ -890,31 +890,20 @@ install(
   EXPORT cudf-exports
 )
 
-install(DIRECTORY ${CUDF_SOURCE_DIR}/include/cudf ${CUDF_SOURCE_DIR}/include/cudf_test
-                  ${CUDF_SOURCE_DIR}/include/nvtext DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
-)
-
-if(CUDF_BUILD_TESTUTIL)
+set(_components_export_string)
+if(TARGET cudftestutil)
   install(
     TARGETS cudftest_default_stream cudftestutil
     DESTINATION ${lib_dir}
     EXPORT cudf-testing-exports
   )
-
-  install(
-    EXPORT cudf-testing-exports
-    FILE cudf-testing-targets.cmake
-    NAMESPACE cudf::
-    DESTINATION "${lib_dir}/cmake/cudf"
-  )
-
-  include("${rapids-cmake-dir}/export/write_dependencies.cmake")
-  rapids_export_write_dependencies(
-    INSTALL cudf-testing-exports
-    "${PROJECT_BINARY_DIR}/rapids-cmake/cudf/export/cudf-testing-dependencies.cmake"
-  )
+  set(_components_export_string COMPONENTS testing COMPONENTS_EXPORT_SET cudf-testing-exports)
 endif()
 
+install(DIRECTORY ${CUDF_SOURCE_DIR}/include/cudf ${CUDF_SOURCE_DIR}/include/cudf_test
+                  ${CUDF_SOURCE_DIR}/include/nvtext DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
+)
+
 if(CUDF_BUILD_STREAMS_TEST_UTIL)
   install(TARGETS cudf_identify_stream_usage_mode_cudf DESTINATION ${lib_dir})
   install(TARGETS cudf_identify_stream_usage_mode_testing DESTINATION ${lib_dir})
@@ -976,21 +965,15 @@ string(
   [=[
 if(testing IN_LIST cudf_FIND_COMPONENTS)
   enable_language(CUDA)
-  if(EXISTS "${CMAKE_CURRENT_LIST_DIR}/cudf-testing-dependencies.cmake")
-    include("${CMAKE_CURRENT_LIST_DIR}/cudf-testing-dependencies.cmake")
-  endif()
-  if(EXISTS "${CMAKE_CURRENT_LIST_DIR}/cudf-testing-targets.cmake")
-    include("${CMAKE_CURRENT_LIST_DIR}/cudf-testing-targets.cmake")
-  endif()
 endif()
 ]=]
 )
 string(APPEND install_code_string "${common_code_string}")
 
 rapids_export(
   INSTALL cudf
-  EXPORT_SET cudf-exports
-  GLOBAL_TARGETS cudf
+  EXPORT_SET cudf-exports ${_components_export_string}
+  GLOBAL_TARGETS cudf cudftestutil
   NAMESPACE cudf::
   DOCUMENTATION doc_string
   FINAL_CODE_BLOCK install_code_string
@@ -1013,23 +996,13 @@ string(APPEND build_code_string "${common_code_string}")
 
 rapids_export(
   BUILD cudf
-  EXPORT_SET cudf-exports
-  GLOBAL_TARGETS cudf
+  EXPORT_SET cudf-exports ${_components_export_string}
+  GLOBAL_TARGETS cudf cudftestutil
   NAMESPACE cudf::
   DOCUMENTATION doc_string
   FINAL_CODE_BLOCK build_code_string
 )
 
-if(CUDF_BUILD_TESTUTIL)
-  export(
-    EXPORT cudf-testing-exports
-    FILE ${CUDF_BINARY_DIR}/cudf-testing-targets.cmake
-    NAMESPACE cudf::
-  )
-  rapids_export_write_dependencies(
-    BUILD cudf-testing-exports "${CUDF_BINARY_DIR}/cudf-testing-dependencies.cmake"
-  )
-endif()
 # ##################################################################################################
 # * make documentation ----------------------------------------------------------------------------