add npm run command for mock validation test

Author: archmoj

package.json

@@ -39,6 +39,7 @@
     "docker": "node tasks/docker.js",
     "pretest": "node tasks/pretest.js",
     "test-jasmine": "karma start test/jasmine/karma.conf.js",
+    "test-mock": "node tasks/test_mock.js",
     "test-image": "node tasks/test_image.js",
     "test-export": "node tasks/test_export.js",
     "test-syntax": "node tasks/test_syntax.js && npm run find-strings -- --no-output",