ck: Build of fresh clone fails due to failing test

I am running mvn clean package on HEAD 17b80cb which fails due to a failing test.

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Test set: com.github.mauricioaniche.ck.NOCTest
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Tests run: 2, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 0.012 s <<< FAILURE! - in com.github.mauricioaniche.ck.NOCTest
shouldDetectChildren  Time elapsed: 0.009 s  <<< FAILURE!
org.opentest4j.AssertionFailedError: expected: <1> but was: <2>
	at com.github.mauricioaniche.ck.NOCTest.shouldDetectChildren(NOCTest.java:19)

This happens on both a JDK11 and JDK16 Maven runner. Similarly, if I run the tests through IntelliJ, this is the only test that fails.