[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

Start in packages/product-json-to-csv/package.json, where the unzip test dependency is declared, then inspect the package's unit tests to check how it is used. Replace the unmaintained library with an actively supported alternative such as unzip-stream, and confirm the product-json-to-csv unit tests still pass.

Scritto dal modello di indicizzazione a partire dal testo della issue.