io.vertx.ext.auth.authentication.Credentials should be a data object …

…interface.

Motivation:

io.vertx.ext.auth.authentication.Credentials is a code generated object, however its implementations are data objects. Generated code declaring Credentials as argument or return type does not accept Credentials implementation since the type is translated to the shim equivalent.

Changes:

Make Credentials a data object.

vertx-auth-common/src/main/java/io/vertx/ext/auth/authentication/Credentials.java

@@ -15,7 +15,7 @@
  */
 package io.vertx.ext.auth.authentication;
 
-import io.vertx.codegen.annotations.VertxGen;
+import io.vertx.codegen.annotations.DataObject;
 import io.vertx.core.http.HttpMethod;
 import io.vertx.core.json.JsonObject;
 
@@ -25,7 +25,7 @@
  *
  * @author Paulo Lopes
  */
-@VertxGen(concrete = false)
+@DataObject
 public interface Credentials {
   /**
    * Implementors should override this method to perform validation. An argument is allowed to