Arvados

New version first commit: https://dev.arvados.org/projects/arvados-workbench-2/repository/revisions/534df712c4cfc3f6574dee1f4906bb7f6cc70be9
Test run: developer-tests-workbench2: #2 ​49/

This is the simplest yet the fastest way to implement this, I would vote for a cleanup ticket for the tree components all over the app as this is really messy.

I noticed that CollectionIcon and FileIcon use the same "LibraryBooks" material ui icon. Let's change what FileIcon uses. I think the one from the material UI icons that works best is the Description icon. Could you make this change?

workbench2/src/components/icon/icon.tsx

export const FileIcon: IconType = (props) => <Description {...props} />;

LGTM with that tweak.