"Nonexistent files" test fails because of quoting style

[phst]

The "nonexistent files" test fails for me because Emacs now uses Unicode quotes by default:

Then I should see error "/missing-test.el` does not exist"
      Test failed: ((should (s-contains\? expected ert-runner-error)) :form (s-contains\? "/missing-test.el` does not exist" "‘/path/to/ert-runner.el/features/project/test/missing-test.el‘ does not exist.
      ") :value nil)

Either you need to bind text-quoting-style or check for either ASCII or Unicode quotes.
(The quote itself is also incorrect; it's an opening quote, not a closing quote.)

[Fuco1]

Fixed in #51.