StreamArrowPythonGroupWindowAggregateFunctionOperatorTest.testFinishBundleTriggeredByCount fails

Error: 02:27:17 02:27:17.025 [ERROR] Tests run: 3, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 0.658 s <<< FAILURE! - in org.apache.flink.table.runtime.operators.python.aggregate.arrow.stream.StreamArrowPythonGroupWindowAggregateFunctionOperatorTest
Error: 02:27:17 02:27:17.025 [ERROR] org.apache.flink.table.runtime.operators.python.aggregate.arrow.stream.StreamArrowPythonGroupWindowAggregateFunctionOperatorTest.testFinishBundleTriggeredByCount  Time elapsed: 0.3 s  <<< FAILURE!
Mar 09 02:27:17 java.lang.AssertionError: 
Mar 09 02:27:17 
Mar 09 02:27:17 Expected size: 8 but was: 6 in:
Mar 09 02:27:17 [Record @ (undef) : +I(c1,0,1969-12-31T23:59:55,1970-01-01T00:00:05),
Mar 09 02:27:17     Record @ (undef) : +I(c2,3,1969-12-31T23:59:55,1970-01-01T00:00:05),
Mar 09 02:27:17     Record @ (undef) : +I(c2,3,1970-01-01T00:00,1970-01-01T00:00:10),
Mar 09 02:27:17     Record @ (undef) : +I(c1,0,1970-01-01T00:00,1970-01-01T00:00:10),
Mar 09 02:27:17     Watermark @ 10000,
Mar 09 02:27:17     Watermark @ 20000]
Mar 09 02:27:17 	at org.apache.flink.table.runtime.util.RowDataHarnessAssertor.assertOutputEquals(RowDataHarnessAssertor.java:110)
Mar 09 02:27:17 	at org.apache.flink.table.runtime.util.RowDataHarnessAssertor.assertOutputEquals(RowDataHarnessAssertor.java:70)
Mar 09 02:27:17 	at org.apache.flink.table.runtime.operators.python.aggregate.arrow.ArrowPythonAggregateFunctionOperatorTestBase.assertOutputEquals(ArrowPythonAggregateFunctionOperatorTestBase.java:62)
Mar 09 02:27:17 	at org.apache.flink.table.runtime.operators.python.aggregate.arrow.stream.StreamArrowPythonGroupWindowAggregateFunctionOperatorTest.testFinishBundleTriggeredByCount(StreamArrowPythonGroupWindowAggregateFunctionOperatorTest.java:326)
Mar 09 02:27:17 	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
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