Add view metrics button to traces

What does this MR do and why?

• Add "View metrics" button to traces
• I've also changed the action buttons variants to be consistent with the other features

Relates to gitlab-org/opstrace/opstrace#2928 (closed)

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

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Before	After

How to set up and validate locally

1. You need a GitLab Ultimate license.
2. Enable the :observability_features feature flag.
3. Apply patch to load local mocks git apply < <(curl -s https://gitlab.com/-/snippets/3740820/raw/main/snippetfile1.txt)
4. Go to http://gdk.test:3443/flightjs/Flight/-/metrics