title: WebFluxTest cannot read matrix variables
body: <p>I am writing a WebFluxTest :</p>
  
  <pre><code>@WebFluxTest(controllers=Example.class)
  
  class ExampleTest  {
      @Autowired
      WebTestClient webTestClient;
      @Test
      public void example(){
  
          webTestClient.get().uri("http://localhost:8080/example/employees/id=1")
                       .exchange()
                       .expectBody().consumeWith(response -&gt; assertTrue(new String(response.getResponseBody(), StandardCharsets.UTF_8).contains(expected)));
      }
  }
  </code></pre>
  
  <p>The code to be tested is:</p>
  
  <pre><code>@Controller
  public class Example {
  
      @GetMapping("/example/employees/{id}")
      @ResponseBody
      public String example(@MatrixVariable("id") int id) {
          ....
      }
  </code></pre>
  
  <p>It is a Spring Boot application with this configuration:</p>
  
  <pre><code>@Configuration
  public class MyConfig implements WebMvcConfigurer {
     @Override
      public void configurePathMatch(PathMatchConfigurer configurer) {
          UrlPathHelper urlPathHelper = new UrlPathHelper();
          urlPathHelper.setRemoveSemicolonContent(false);
          configurer.setUrlPathHelper(urlPathHelper);
      }
  ...
  </code></pre>
  
  <p>The output is:
  "status":400,"error":"Bad Request","message":"Missing matrix variable 'id' for method parameter of type int"}</p>