fix(test): update assertFile syntax

Fix failing tests by updating the assertFile syntax from
yeoman-generator

Closes #554

Author: eggers

test/test-file-creation.js

@@ -209,9 +209,9 @@ describe('Angular generator', function () {
       });
       angular.run([], function (){
         angularView.run([], function () {
-          helpers.assertFiles([
+          helpers.assertFile(
             ['app/views/foo.html']
-          ]);
+          );
           done();
         });
       });
@@ -230,9 +230,9 @@ describe('Angular generator', function () {
       });
       angular.run([], function (){
         angularView.run([], function () {
-          helpers.assertFiles([
+          helpers.assertFile(
             ['app/views/foo/bar.html']
-          ]);
+          );
           done();
         });
       });