Add reusable TokenValidityBadge component

What does this MR do and why?

Add reusable TokenValidityBadge component

This commit adds a new reusable component for displaying the validity status of secret tokens found in vulnerabilities. The component shows different colored badges based on the token's status (active, inactive, or unknown).

• Create TokenValidityBadge in shared security reports
• Implement status-based styling and labeling
• Support three states: active, inactive, and unknown
• Use GitLab UI label component for consistent styling

Changelog: added EE: true

References

addresses [Follow-up] Create validity-check-badge Compone... (#537760 - closed) • Radu Birsan • 18.0

Screenshots or screen recordings

How to set up and validate locally

1. Go to Secure > Security Configuration for a project and enable Pipeline Secret Detection

2. Create or add a secret like glpat-00000000000000000000 anywhere inside the project and trigger a pipeline so you that an entry gets generated in Secure > Vulnerability Report

3. Navigate to the Vulnerability Finding Page you just generated and note the id at the top of the url, in rails console run to find the vulnerability_occurrence_id:

Vulnerability.find(<id>).finding.id

4. in rails console enable the feature flag

 Feature.enable(:validity_checks)

5. in rails console create a vulnerability finding token status

 Vulnerabilities::FindingTokenStatus.create(vulnerability_occurrence_id: <vulnerability_occurrence_id>, status: "active")

6. Refresh finding page and you should see the badge now

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