Remove unused vuln pipeline components

What does this MR do and why?

Related #438235 (closed)

This is part of the frontend cleanup after the pipeline_security_dashboard_graphql feature flag removal.

There will be more MRs to follow as the total cleanup is very big. This MR follows Remove security_dashboard from pipeline_securit... (!167903 - merged) , Remove unused security_dashboard_vuex and loadi... (!168496 - merged), and Remove pipeline filters and spec (!168498 - merged).

Check #438235 (closed) for a list of the full cleanup.

This MR removes a couple unused components, their specs, and updates the translations.

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