With contract like this
```
// output message of the contract
outputMessage {
// destination to which the output message will be sent
sentTo 'verifications'
// the body of the output message
body(
eligible: true
)
headers {
header("contentType", applicationJsonUtf8())
}
}
```
the generated test produces
```
ContractVerifierMessage response = contractVerifierMessaging.receive("verifications");
assertThat(response.getHeader("contentType")).isEqualTo("application/json;charset=UTF-8");
```
The headers in the response is a MimeType not a String so the equality check fails.
fixes#297
4ddae01bf9