Use node for dropzone dependencies

How we include dropzone is not great right now, because we have to update it elsewhere and it would be cool if we didn't have to do that. And we have node in the project and it's not leaving anytime soon so I think it doesn't hurt

Also sonarqube whines about not having integrity checks on the sources which is very valid

The issue does not name the current dropzone inclusion or any tests. Start by locating how dropzone is currently included and reviewing the project's existing Node setup; then determine how dependency updates and SonarQube integrity checks should be handled. Done means dropzone is managed through Node and the source integrity warning is resolved.

Written by the indexing model from the issue text.