static HttpResponse ofJson(Object content) {
        return ofJson(HttpStatus.OK, content);
    }
Creates a new HTTP response with the specified {@code content} that is converted into JSON using the
default {@link ObjectMapper}.

@throws IllegalArgumentException if failed to encode the {@code content} into JSON.
@see JacksonObjectMapperProvider
core/src/main/java/com/linecorp/armeria/common/HttpResponse.java