"test-helper.el" isn't a library intended to be loaded with `require`.
Instead it is loaded with `load`. Because of that, it is confusing to
provide a feature using `provide` anyway. And because around 70 other
packages come with a file named "test-helper.el" and several dozen of
those still provide the feature `test-helper`, this also leads to a,
admittedly somewhat theoretical, feature conflict.
This is also discussed at https://github.com/rejeep/ert-runner.el/issues/38.
Jonas Bernoulli
Elis Axelsson