KAFKA-12790: Fix SslTransportLayerTest.testUnsupportedTlsVersion with JDK 16

[ijuma]

Committer Checklist (excluded from commit message)

• Verify design and implementation
• Verify test coverage and CI build status
• Verify documentation (including upgrade notes)

[ijuma]

@rajinisivaram we have one test failure (testUnsupportedTlsVersion) in the clients module with JDK 16:

Failed authentication with localhost/127.0.0.1 (SSL handshake failed) (org.apache.kafka.common.network.Selector:616)
[2021-03-26 06:37:05,312] ERROR Connection with /127.0.0.1 disconnected (org.apache.kafka.common.network.Selector:606)
java.io.EOFException: EOF during handshake, handshake status is NEED_UNWRAP
at org.apache.kafka.common.network.SslTransportLayer.handshakeUnwrap(SslTransportLayer.java:525)
at org.apache.kafka.common.network.SslTransportLayer.doHandshake(SslTransportLayer.java:368)
at org.apache.kafka.common.network.SslTransportLayer.handshake(SslTransportLayer.java:291)
at org.apache.kafka.common.network.KafkaChannel.prepare(KafkaChannel.java:178)
at org.apache.kafka.common.network.Selector.pollSelectionKeys(Selector.java:543)
at org.apache.kafka.common.network.Selector.poll(Selector.java:481)
at org.apache.kafka.common.network.NioEchoServer.run(NioEchoServer.java:211)

org.opentest4j.AssertionFailedError: Condition not met within timeout 15000. Metric not updated failed-authentication-total expected:<1.0> but was:<0.0> ==>
Expected :true
Actual :false
at org.junit.jupiter.api.AssertionUtils.fail(AssertionUtils.java:55)
at org.junit.jupiter.api.AssertTrue.assertTrue(AssertTrue.java:40)
at org.junit.jupiter.api.Assertions.assertTrue(Assertions.java:193)
at org.apache.kafka.test.TestUtils.lambda$waitForCondition$3(TestUtils.java:303)
at org.apache.kafka.test.TestUtils.retryOnExceptionWithTimeout(TestUtils.java:351)
at org.apache.kafka.test.TestUtils.retryOnExceptionWithTimeout(TestUtils.java:319)
at org.apache.kafka.test.TestUtils.waitForCondition(TestUtils.java:300)
at org.apache.kafka.common.network.NioEchoServer.waitForMetrics(NioEchoServer.java:196)

With JDK 15:

[2021-03-26 06:38:01,908] ERROR Failed authentication with /127.0.0.1 (SSL handshake failed) (org.apache.kafka.common.network.Selector:616)
[2021-03-26 06:38:01,908] ERROR Failed authentication with localhost/127.0.0.1 (SSL handshake failed) (org.apache.kafka.common.network.Selector:616)

Any ideas?

[ijuma]

Filed https://issues.apache.org/jira/browse/KAFKA-12790 to track this.