fix(ui): add missing namespace when tagging a job version

[sevensolutions]

Description

This PR adds the missing namespace to the server request when tagging a job version from the UI.

Testing & Reproduction steps

See #26185

Links

Fixes #26185

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
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• Documentation If the change impacts user-facing functionality such as the CLI, API, UI,
  and job configuration, please update the Nomad product documentation, which is stored in the
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  Please also consider whether the change requires notes within the upgrade
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Reviewer Checklist

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Changes to Security Controls

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

[pkazmierczak]

LGTM, I tested your changes locally and it indeed fixes the issue. Thanks for the contribution, @sevensolutions!

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