[tests] Add test all script (#3106)
[tests] Add test all script (#3106)

This PR focuses on adding the `test` script to the `package.json` : )

## Main problem 

Previously there was no `test` script that includes all the tests

<img width="924" alt="Screen Shot 2019-10-01 at 8 13 13 AM" src="https://user-images.githubusercontent.com/16585386/65968681-26f6a080-e429-11e9-9f29-c6fd343fdb12.png">

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