pyspark.mllib.clustering fails on JDK11

$ build/sbt -Phadoop-3.2 test:package
$ python/run-tests --testnames 'pyspark.mllib.clustering' --python-executables python
...
File "/Users/dongjoon/APACHE/spark-master/python/pyspark/mllib/clustering.py", line 386, in __main__.GaussianMixtureModel
Failed example:
    abs(softPredicted[0] - 1.0) < 0.001
Expected:
    True
Got:
    False
**********************************************************************
File "/Users/dongjoon/APACHE/spark-master/python/pyspark/mllib/clustering.py", line 388, in __main__.GaussianMixtureModel
Failed example:
    abs(softPredicted[1] - 0.0) < 0.001
Expected:
    True
Got:
    False
**********************************************************************
   2 of  31 in __main__.GaussianMixtureModel
***Test Failed*** 2 failures.