Wrong content-type when using Kotlin coroutines in RESTEasy Reactive

Describe the bug

I have changed a web endpoint from returning a Mutiny Uni to using a suspend function.

I would expect that the content type stays the same (application/json)

The content-type is application/octet-stream

Returns application/json:

@Path("/test")
class TestController{

    @GET
    fun test() = Uni.createFrom().item(MyObject("hello"))
}

data class MyObject(val test:String)

Returns application/octet-stream:

@Path("/test")
class TestController{

    @GET
    suspend fun test() = MyObject("hello")
}

data class MyObject(val test:String)

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