Update playground tests with playground configuration

Format tests with gofmt

(cherry picked from commit 3afa9bf)

Author: raphaelzoellner

graphcoolPlayground_test.go

@@ -62,9 +62,11 @@ func TestRenderPlayground(t *testing.T) {
 			req.Header.Set("Accept", tc.accept)
 
 			h := handler.New(&handler.Config{
-				Schema:     &testutil.StarWarsSchema,
-				GraphiQL:   false,
-				Playground: tc.playgroundEnabled,
+				Schema:   &testutil.StarWarsSchema,
+				GraphiQL: false,
+				Playground: &handler.PlaygroundConfig{
+					Enabled: tc.playgroundEnabled,
+				},
 			})
 
 			rr := httptest.NewRecorder()

handler_test.go

@@ -245,7 +245,7 @@ func TestHandler_BasicQuery_WithFormatErrorFn(t *testing.T) {
 	customFormattedError := gqlerrors.FormattedError{
 		Message: resolverError.Error(),
 		Locations: []location.SourceLocation{
-			location.SourceLocation{
+			{
 				Line:   1,
 				Column: 2,
 			},