The script is needed to run the new Docker-based Jenkins job that runs daily and targets beta cluster.
selenium-test script and NPM packages are dependencies. selenium-daily now just calls selenium-test.
selenium-daily might seem redundant, but it provides flexibility. In case a
repository does not want to run all tests daily, that's easily fixed by updating the
selenium-daily script.
Bug: T188742
Change-Id: I35c93ff1897afc4b9e66703a1acf765e3fe7b643
