feat(api/consul): allow configuring identities for sidecar_task

[3nprob]

Description

Allow configuring non-default identity for sidecar_task.

Testing & Reproduction steps

Sample job spec excerpt:

job "foo" {
  group "foo" {
    consul {}
    service {
      identity {
        aud = ["consul.io"]
      }
      connect {
        sidecar_service {}
        sidecar_task {
          identity {
            aud = ["consul.io"]
          }
        }
      }
    }
    task "foo" {
      # ...
    }
  }
}

Links

Fixes: #24660

Contributor Checklist

• Changelog Entry If this PR changes user-facing behavior, please generate and add a
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• 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
  the website README for docs guidelines. Please also consider whether the
  change requires notes within the upgrade guide.

Reviewer Checklist

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  in the majority of situations. The main exceptions are long-lived feature branches or merges where
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  within the public repository.

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[3nprob]

This has been manually tested. ✔️

[aimeeu]

Thanks for updating the docs. Approving the docs content only.

[3nprob]

Rebased on main and had to resolve merge-conflict in docs. No further changes.

[aimeeu]

Docs approval

[jrasell]

Hi @3nprob and thanks for raising this PR.

Before I perform manual testing and thorough code review, would it be possible to add units tests for the new functionality covered? Once these are added I'll go ahead and review. Thanks.

[tgross]

(Internal ref https://hashicorp.atlassian.net/browse/NMD-439)

[aimeeu]

Note: The Nomad docs content is scheduled to move to web-unified-docs repo on Tuesday 18 Nov. If this PR does not merge before the move, I will take care of creating the docs PR in the new repo.

[aimeeu]

Since the docs content has migrated to the web-unified-docs repo, the updates in this PR need to be recreated in the other repo. I can do the docs update, once Eng decides which release this is going into.

[tgross]

I can do the docs update, once Eng decides which release this is going into.

It's a minor new feature so it'd go into 1.11.x assuming this lands before next spring

[3nprob]

Thanks for follow-up.

I've addressed the review feedback and rebased on main.

[tgross]

LGTM!

I've reviewed and this is addressed

[tgross]

I'll open a PR to migrate over the docs portion of this.

[tgross]

Docs PR: hashicorp/web-unified-docs#1448