@Test
void append() {

    var headers = new HeaderMap();
    HttpString name = new HttpString("client-id");
    headers.put(name, "client1");
    var builder = new StringBuilder();
    var param = new HeaderLogParam(name, headers.get(name));
    param.append(builder, Set.of(), 1000);
    assertThat(builder.toString()).isEqualTo("client1");
    headers.add(name, "client2");
    builder = new StringBuilder();
    param = new HeaderLogParam(name, headers.get(name));
    param.append(builder, Set.of(), 1000);
    assertThat(builder.toString()).isEqualTo("[client1, client2]");
}