Update to use rapids-export(COMPONENTS) feature.

[robertmaynard]

Description

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 issues with not finding GTest targets

Fixes #12976

Checklist

• I am familiar with the Contributing Guidelines.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.

[vyasr]

Is the export name being set here clashing with the "nice" export name in rapids-cmake, leading to trying to install an export set that doesn't actually exist?

[robertmaynard]

Is the export name being set here clashing with the "nice" export name in rapids-cmake, leading to trying to install an export set that doesn't actually exist?

Maybe? What failures are you looking at. I can't see what is going wrong in the wheel builds

[vyasr]

It's failing with

    -- Configuring done (22.5s)
    CMake Error: INSTALL(EXPORT) given unknown export "cudf-testing-exports"
    -- Generating done (0.2s)

(you have to expand some in-text dropdowns or open the raw log).

[robertmaynard]

It's failing with

    -- Configuring done (22.5s)

    CMake Error: INSTALL(EXPORT) given unknown export "cudf-testing-exports"

    -- Generating done (0.2s)

(you have to expand some in-text dropdowns or open the raw log).

The "nice" name is only used for the files rapids-CMake generates.

What this looks like is that for some builds we disable cudf test util from being built, but we are always trying to export it.
We will need to update the PR to only add the COMPONENTS arguments to rapids_export when cudf test util is being built.

[vyasr]

Good catch. Pushed the fix.

[jlowe]

Verified that pulling in this fix resolves #12976.

[robertmaynard]

/merge