[BUG] Sporadic HDBSCAN C++ unit test failure

[dantegd]

Describe the bug Seen at least in nightly CI:

[ RUN      ] HDBSCANTest/HDBSCANTestF_Int.Result/3
Label prop iterations: 10
Label prop iterations: 8
Label prop iterations: 5
Label prop iterations: 5
Label prop iterations: 3
Iterations: 5
1377,143,148,20,247,1003
/workspace/.conda-bld/work/cpp/test/sg/hdbscan_test.cu:124: Failure
Value of: score >= 0.85
  Actual: false
Expected: true
[  FAILED  ] HDBSCANTest/HDBSCANTestF_Int.Result/3, where GetParam() =  (196 ms)

From the job of March 21, seen in CUDA 11.2 and 11.4: https://gpuci.gpuopenanalytics.com/job/rapidsai/job/gpuci/job/cuml/job/branches/job/cuml-gpu-matrix-branch-22.04/CUDA=11.4,GPU_LABEL=driver-450,LINUX_VER=ubuntu18.04,PYTHON_VER=3.8/26/console

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[github-actions[bot]]

This issue has been labeled inactive-90d due to no recent activity in the past 90 days. Please close this issue if no further response or action is needed. Otherwise, please respond with a comment indicating any updates or changes to the original issue and/or confirm this issue still needs to be addressed.