HttpClientTest shouldCloseConnectionOnTimeoutDuringContentReceive is flaky

[splitfeed]

The test randomly seems to fail both locally and on Travis, but I fail to see any obvious reason for it.

org.mockito.exceptions.verification.TooLittleActualInvocations: 
consumer.accept(
    "/hello/servertest/slowBody"
);
Wanted 11 times:
-> at se.fortnox.reactivewizard.client.HttpClientTest.shouldCloseConnectionOnTimeoutDuringContentReceive(HttpClientTest.java:562)
But was 10 times:
-> at se.fortnox.reactivewizard.client.HttpClientTest.lambda$createTestServer$12(HttpClientTest.java:509)