Vanilla, sync-over-async response type conversion bug

[XiaofeiCao]

When:

1. Vanilla
2. Content-Type: text/powershell
3. response is binary
4. async-stack

XXWithResponse method implementation be:

// async method
public Mono<Response<Flux<ByteBuffer>>> putWithBinaryJsonRequestAndBinaryTextResponseWithResponseAsync(String runbookName,
        Flux<ByteBuffer> binaryContent, long contentLength, Context context) {
  // ignore implementation
}

//sync method
public Response<BinaryData> putWithBinaryJsonRequestAndBinaryTextResponseWithResponse(String runbookName,
    Flux<ByteBuffer> binaryContent, long contentLength, Context context) {
    return putWithBinaryJsonRequestAndBinaryTextResponseWithResponseAsync(runbookName, binaryContent, contentLength,
        context).block();
}

There's response type conversion bug(Response<Flux<ByteBuffer>> -> Response<BinaryData>).

Not urgent, as current vanilla generated SDKs(storage, etc) are on sync-stack already, and I haven't seen such case.