I get this test failure when running

gradle check

locally:

java.lang.AssertionError: expected: a value that throws kotlin.Throwable that is a java.net.UnknownHostException
but was: a org.eclipse.jetty.websocket.api.exceptions.UpgradeException
	at com.natpryce.hamkrest.assertion.AssertKt.assertThat(assert.kt:19)
	at com.natpryce.hamkrest.assertion.AssertKt.assertThat$default(assert.kt:16)
	at org.http4k.websocket.BlockingWebsocketClientContract.exception is thrown on connection error(BlockingWebsocketClientContract.kt:47)

with

------------------------------------------------------------
Gradle 8.1.1
------------------------------------------------------------

Build time:   2023-04-21 12:31:26 UTC
Revision:     1cf537a851c635c364a4214885f8b9798051175b

Kotlin:       1.8.10
Groovy:       3.0.15
Ant:          Apache Ant(TM) version 1.10.11 compiled on July 10 2021
JVM:          11.0.19 (Eclipse Adoptium 11.0.19+7)
OS:           Linux 5.19.0-42-generic amd64

from Docker image

gradle:8.1.1-jdk11-alpine

.