Frontend: Scaffold Security labels tab in project-level Security configuration page

Scaffold out a blank-ish Category label application screen:

🎨 design: #547963[Security_configuration-_project-level_-_apply_label.png]

• 🧵 What role/permission(s) does a user need to have to create and edit labels?
  • to create/edit/delete security labels, a user will need a new permission
  • a user that can view a project can view its security labels

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• add a Security labels tab to the page at [PROJECT URL]/-/security/configuration (after the existing Security testing and Vulnerability management tabs)
• only show the tab if user has sufficient permissions, the licensed feature is available, and the feature flag is enabled
• add description text