Backport of [ui] Ember test suite upgraded into release/1.8.x

[hc-github-team-nomad-core]

Backport

This PR is auto-generated from #24020 to be assessed for backporting due to the inclusion of the label backport/1.8.x.

🚨

Warning automatic cherry-pick of commits failed. If the first commit failed,
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The person who merged in the original PR is:
@philrenaud
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

merge conflict error: POST https://api.github.com/repos/hashicorp/nomad/merges: 409 Merge conflict []

The below text is copied from the body of the original PR.

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Resolves #24019
Resolves https://github.com/hashicorp/nomad/security/code-scanning/674

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Overview of commits

• e65767f

[hashicorp-cla-app]

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1 out of 2 committers have signed the CLA.

• philrenaud
• temp

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