Finishing update begun in https://github.com/spree/spree/issues/3671

The change in https://github.com/spree/spree/issues/3671 helps ensure that spree 1.3.3 gets installed, but it appears that when multiple versions are installed, the `spree` command defaults to the most recent version. This way we'll make sure it's the 1.3.3 spree that's running the initialization for the new rails app.