tests inside `src/helpers` are not running

[zvictor]

The test file https://github.com/Quadric/radiaction/blob/8566ecd81ba08edea75fe59e5caaed2e662bfc17/packages/radiaction/src/helpers/keepName.test.js#L7 should be running with ava, but it's not.

I tried many different globs in the configs, but none worked. That's the one we are going with for now:
https://github.com/Quadric/radiaction/blob/8566ecd81ba08edea75fe59e5caaed2e662bfc17/packages/radiaction/package.json#L58

it might be related to this: avajs/ava#1319