UnionExec array and nested array support

[rwlee]

Resolves #1459

Depends on rapidsai/cudf#9130 for unionByName list of struct support. Approved but not merged yet.

Adds type support for arrays and nested arrays for union, unionAll, unionByName. Also includes better UnionExec testing for nested types.

[razajafri]

build

[jlowe]

Curious, this depends on a cudf feature that hasn't been merged but the tests pass. This makes me think the tests aren't sufficiently exercising the code, otherwise a test should have failed without the requisite cudf feature.

[ttnghia]

Curious, this depends on a cudf feature that hasn't been merged but the tests pass. This makes me think the tests aren't sufficiently exercising the code, otherwise a test should have failed without the requisite cudf feature.

Yeah, this looks dangerous to me too 😃

[jlowe]

Converting this to a draft so this doesn't get accidentally merged by a passerby until this mystery is solved.

[rwlee]

build

[rwlee]

I can turn this test error on and off with a very clear change within cudf, but for whatever reason the followup build still passed. The followup build was started before the PR was merged, but it was pretty close timing. If the blossom CI was delayed pulling the snapshot it may have picked up a cudf snapshot with the fix in it. Looking into it tomorrow, but with locally tests demonstrating cause and effect I think this is good to reopen/merge...

[rwlee]

Confirmed while testing with different versions of the snapshot jars, the new test correctly hits the dependent interleave column functionality.

[razajafri]

Approve the plugin side changes assuming it has been verified that this patch fails with older versions of cudf

[rwlee]

Approve the plugin side changes assuming it has been verified that this patch fails with older versions of cudf

Verified offline with different snapshot builds. Fails with cudf-21.10.0-20210902.122036-35-cuda11.jar and cudf-21.10.0-20210902.063732-34-cuda11.jar, but passes with cudf-21.10.0-20210903.122002-36-cuda11.jar