Tslint doesn't exclude "tests" directory

Summary

Tslint doesn't exclude test directory in projects that use configuration (this project).

Steps to reproduce

Check in any project that uses @openstapps/configuration package, or start a new project with tslint.js file:

{
  "extends": "./node_modules/@openstapps/configuration/tslint.json"
}

What is the current bug behavior?

Files in tests directory are checked by tslint, what should be disabled by tslint.json but it's not. See core-tools!29 (merged) (or core-tools!29 (comment 405782632))

What is the expected correct behavior?

Files in tests directory and it's sub-directories should not be checked by tslint.

Possible fixes

Path should be adjusted to "../../../test/**/*".