With 1.0.0-RC1, the Client now sends the Content-Type header as application/graphql+json

We're trying to override the headers here, but it has no affect:

HttpGraphQlClient.builder(webClient) .url(url) .headers { header -> header.contentType = MediaType.APPLICATION_JSON } .build() graphQlClient.documentName(documentName) .variables(variables) .retrieve("myQuery") .toEntityList(myQuery::class.java) 

It's still coming over as application/graphql+json.

We need to do this, as the the Apollo graphql gateway we're using does not accept the graphql header.
Error: POST body missing, invalid Content-Type, or JSON object has no keys. (it's not the other two).