Improve use of isinstance.

[bdice]

This PR combines a few isinstance checks to reduce the complexity of the logic.

Note: Some of these were identified by https://codereview.doctor/rapidsai/cudf. In some places, the bot correctly identified a problem but its suggestions were invalid or incomplete. I identified steps for improvement beyond what the bot suggested for most of these cases.

[codecov]

Codecov Report

Merging #10734 (87a73e4) into branch-22.06 (3c13ef1) will increase coverage by 0.05%.
The diff coverage is 90.96%.

❗ Current head 87a73e4 differs from pull request most recent head 8e0c9e3. Consider uploading reports for the commit 8e0c9e3 to get more accurate results

@@               Coverage Diff                @@
##           branch-22.06   #10734      +/-   ##
================================================
+ Coverage         86.33%   86.39%   +0.05%     
================================================
  Files               140      142       +2     
  Lines             22289    22300      +11     
================================================
+ Hits              19244    19266      +22     
+ Misses             3045     3034      -11     

Impacted Files	Coverage Δ
python/cudf/cudf/_fuzz_testing/json.py	0.00% <0.00%> (ø)
python/cudf/cudf/core/_base_index.py	85.45% <ø> (ø)
python/cudf/cudf/core/dtypes.py	97.30% <ø> (ø)
python/cudf/cudf/core/index.py	92.31% <ø> (ø)
python/cudf/cudf/core/tools/numeric.py	89.24% <ø> (ø)
python/cudf/cudf/testing/dataset_generator.py	73.25% <ø> (ø)
python/cudf/cudf/utils/cudautils.py	65.74% <ø> (+5.90%)	⬆️
python/cudf/cudf/utils/gpu_utils.py	50.00% <0.00%> (-4.29%)	⬇️
python/cudf/cudf/utils/ioutils.py	79.60% <ø> (ø)
python/cudf/cudf/utils/utils.py	90.35% <ø> (+0.06%)	⬆️
... and 40 more

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[galipremsagar]

@gpucibot merge