Tests outside of src folder shouldn't be run

Created by: gaelollivier

The README.md says: The .test.js / .spec.js files (or the __tests__ folders) can be located at any depth under the src top level folder.

However, if I create a .spec.js in a e2e folder at the root of the project, it is still executed by npm test

I guess that's a bug. Right now I can workaround by overriding the testPathPattern parameter in my package.json: react-scripts test --env=jsdom --testPathPattern ./src\/.*