@Test
    void testUnpooledResponsePooledSubscriber() throws Exception {
        final BlockingWebClient client = BlockingWebClient.of(server.httpUri());

        final AggregatedHttpResponse response = client.execute(
                RequestHeaders.of(HttpMethod.GET, "/pooled-unaware"));

        assertThat(response.status()).isEqualTo(HttpStatus.OK);
        assertThat(response.contentUtf8()).isEqualTo("pooled content");
        await().untilAsserted(() -> assertThat(releasedByteBuf.get().refCnt()).isZero());
    }
User-agent header should be overridden by ClientOption.HTTP_HEADER
core/src/test/java/com/linecorp/armeria/client/HttpClientIntegrationTest.java