Migrate the Security pipeline tab to the unified Vue app

This makes the necessary changes for the Security tab to function properly in the unified Vue pipeline tabs app.

How to set up and validate locally

1. Enable the pipeline_tabs_vue feature flag.

   Feature.enable(:pipeline_tabs_vue)

2. Make sure your GDK instance has an EE license.
3. Navigate to a pipeline's page in a project that has security scans setup.
   • The Security tab's content should render and actions should work properly.

Note: There is a concurrent initiative which migrates the Security tab to GraphQL instead of the current Vuex-based report. This migration is being worked on behind the :pipeline_security_dashboard_graphql feature flag. The tab should work properly with any combination of the two feature flags.

Related to #360795 (closed)