Fix job_run to show appropriate namespace in web UI link

[nipunn1313]

Description

Fix the UI link to show the appropriate namespace

Example here of "old" behavior, where it was incorrectly showing default namespace.

% nomad run ../services/big-brain/pre-pull-images.nomad
Job registration successful

==> View this job in the Web UI: https://nomad.prod.cvx.is:443/ui/jobs/pre-pull-big-brain@default

Testing & Reproduction steps

nomad run something not in the default namespace

Links

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[gulducat]

heya @nipunn1313, thanks for the PR!

I believe this resolves the issue for jobs that have namespace defined within the job specification, but it's also possible to specify the namespace on the CLI:

nomad job run -namespace='some-other-ns' job.nomad.hcl

which is what c.Meta.namespace reflects, so I think this change breaks that case.

[nipunn1313]

Yeah - I'm realizing we probably want to prioritize the CLI and then if CLI is missing - use the namespace within the job specification.

[nipunn1313]

This test is actually writing to nomad - I don't think this is what we want - going to remove it.