@Test
  void encodedQueryParam() throws Exception {
    server.enqueue(new MockResponse());

    final TestInterfaceAsync api = newAsyncBuilder().target("http://localhost:" + server.getPort());

    final CompletableFuture<?> cf = api.encodedQueryParam("5.2FSi+");

    assertThat(server.takeRequest()).hasPath("/?trim=5.2FSi%2B");

    checkCFCompletedSoon(cf);
  }
The type of a parameter value may not be the desired type to encode as. Prefer the interface
type.
okhttp/src/test/java/feign/okhttp/OkHttpClientAsyncTest.java