fix: routing for goldfish to work with nginx

[trevorwhitney]

What this PR does / why we need it:

The goldfish ui was not working correctly because of the subpath rewrite rule we have in the nginx used for the loki directory in front of it. That rule was only rewriting urls in html assets, and not handling fetch() calls. This PR fixes the fetch() calls used by goldfish to use the absolutePath() helper so urls are correctly rewritten for the nginx environment.

Special notes for your reviewer:

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• Title matches the required conventional commits format, see here
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