add defaults to create new script

[johrstrom]

When you create a new script, we should add some form defaults.

I'm thinking these 2 as a starting place. Note that cluster is a computed value.

title: 'the title that was given'
cluster:
  - job_clusters.reject { |c| c.kubernetes? || c.linux_host? || c.systemd? }
form:
  - auto_accounts

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[johrstrom]

This is a duplicate of #2650.

[johrstrom]

I meant it's a duplicate of #3099 lol. 2650 is this ticket.