Reverting to friendlier Vue full build

Hi friends!

This is a small release that reverts a change made in 0.30.0 related to Vue and a "full" build. See #769 for more details.

To upgrade:

1. Update your package.json file: set the @symfony/webpack-encore version to ^0.30.1.

2. Run yarn upgrade!

v0.30.0...v0.30.1

Happy packing!