private static Step<HttpObject> expectJsonSeqContents(Object publisherOrStream) throws Exception {
        return expectJsonSeqContents(publisherOrStream, JSON_SEQ_HEADERS, DEFAULT_TRAILERS);
    }
{@link HttpData} instances which are expected to be produced by the
{@link JacksonResponseConverterFunction} when the function gets the
{@link #TEST_STRINGS} as input.
core/src/test/java/com/linecorp/armeria/server/annotation/JacksonResponseConverterFunctionTest.java