Fix Javadoc in MockHttpServletRequestBuilder

Class-level Javadoc for MockHttpServletRequestBuilder now correctly
refers to MockMvcRequestBuilders instead of MockMvcBuilders.

Issue: SPR-12393

spring-test/src/main/java/org/springframework/test/web/servlet/request/MockHttpServletRequestBuilder.java

@@ -60,7 +60,7 @@ import org.springframework.web.util.UriUtils;
  * requests in {@link MockMvc}.
  *
  * <p>Application tests will typically access this builder through the static factory
- * methods in {@link org.springframework.test.web.servlet.setup.MockMvcBuilders}.
+ * methods in {@link MockMvcRequestBuilders}.
  *
  * @author Rossen Stoyanchev
  * @author Arjen Poutsma