java.lang.NullPointerException when calling some extension methods

It is possible to raise a java.lang.NullPointerException on some methods of the gradleTestSets.testSets extension. Examples below.

// build.gradle

gradleTestSets {
    testSets {
        main {
            augmentMessageChecksForVersionFromDefault('8.12.1', 'some pattern')
        }
    }
}

// build.gradle

gradleTestSets {
    testSets {
        main {
            augmentMessageChecksForVersionFromDefault('8.12.1', ['some pattern'])
        }
    }
}