- updates unit test to support lower bounded wildcards

Author: baywet

src/test/java/com/microsoft/graph/http/MockHttpProvider.java

@@ -59,7 +59,7 @@ public MockHttpProvider(final ISerializer serializer,
 
     @Override
     public <Result, BodyType> void send(IHttpRequest request,
-                                        ICallback<Result> callback,
+                                        ICallback<? super Result> callback,
                                         Class<Result> resultClass,
                                         BodyType serializable) {
         Result result = null;

src/test/java/com/microsoft/graph/requests/extensions/GraphServiceClientTest.java

@@ -176,7 +176,7 @@ public ISerializer getSerializer() {
             }
 
             @Override
-            public <Result, BodyType> void send(IHttpRequest request, ICallback<Result> callback,
+            public <Result, BodyType> void send(IHttpRequest request, ICallback<? super Result> callback,
                     Class<Result> resultClass, BodyType serializable) {
                 // do nothing
             }