Standardize karma start across packages. (#272)
Standardize karma start across packages. (#272)

For some reason the converter is throwing an internalBinding error when running karma from integration tests.. this is the only difference I see (all are running on Node 10, the yarn.lock and package.json files have the same karma-browserstack-launcher dependency).

DEV

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/tensorflow/tfjs-converter/272)
<!-- Reviewable:end -->

tensorflow/tfjs-converter,tensorflow/tfjs,tensorflow/tfjs-converter,tensorflow/tfjs-converter,tensorflow/tfjs,tensorflow/tfjs-converter,tensorflow/tfjs,tensorflow/tfjs,tensorflow/tfjs,tensorflow/tfjs-converter,tensorflow/tfjs,tensorflow/tfjs,tensorflow/tfjs,tensorflow/tfjs