add the ability to launch scripts

[johrstrom]

Fixes #2576 by actually launching the job once you press the 'Launch' button in the scripts#show page.

In draft at the moment because it depends on #2661 and I'll need to rebase once that's merged.

You can use the same script form as below. Note that your directory will have to be different and you'll actually need to provide a shell script in that directory.

---
title: 'some title'

form:
  - auto_accounts
  - auto_scripts

attributes:
  auto_scripts:
    directory: '/users/PZS0714/johrstrom/ondemand/dev/dashboard/data/projects/2'

┆Issue is synchronized with this Asana task by Unito

[johrstrom]

This is too hard to rebase apparently so I'm just going to cherrypick the commit in a different branch.