addSauceLabsTestName = (testName, cfg) =>
  cfg.sauceLabs
    ? {
        ...cfg,
        sauceLabs: {
          ...cfg.sauceLabs,
          testName
        }
      }
    : {...cfg}
Adds a name for the tests, reflected in SauceLabs' UI. Returns new Karma
config.

Does not add a test name if the `sauceLabs` prop of `cfg` is falsy (which
would imply that we're not running tests on SauceLabs).

@param {string} testName - SauceLabs test name
@param {object} cfg - Karma config.
@returns {object} New Karma config