[product-json-to-csv] Use another unzip library

In our unit tests we are using [unzip](https://github.com/commercetools/nodejs/blob/master/packages/product-json-to-csv/package.json#L62) module which comes from [this repo](https://github.com/EvanOxfeld/node-unzip) and has many open PRs, issues and [is not maintained anymore](https://github.com/EvanOxfeld/node-unzip/issues/95).

We should switch to some other library which has an active support, for example:
https://github.com/mhr3/unzip-stream