[WIP] [NMD-822] support deployments for system jobs

[gregone]

Enables deployments in the UI for system jobs

Description

Testing & Reproduction steps

Links

Contributor Checklist

• Changelog Entry If this PR changes user-facing behavior, please generate and add a
  changelog entry using the make cl command.
• Testing Please add tests to cover any new functionality or to demonstrate bug fixes and
  ensure regressions will be caught.
• Documentation If the change impacts user-facing functionality such as the CLI, API, UI,
  and job configuration, please update the Nomad website documentation to reflect this. Refer to
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  change requires notes within the upgrade guide.

Reviewer Checklist

• Backport Labels Please add the correct backport labels as described by the internal
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• If a change needs to be reverted, we will roll out an update to the code within 7 days.

Changes to Security Controls

Are there any changes to security controls (access controls, encryption, logging) in this pull request? If so, explain.

[philrenaud]

Good stuff!

[pkazmierczak]

🎉
Thanks for helping out, @gregone!

[jrasell]

@gregone and @philrenaud; I plan on merging this PR in despite the failure as it looks to be a persistent flake/error unrelated to this work. Does that sound right?

[philrenaud]

@jrasell yep, sounds good to me.