Improve accessibility for commit list items

The following discussion from !196492 (merged) should be addressed:

• @a_akgun started a discussion: (+2 comments)

  @ms.mondrian optional: The overflow menu items don't have proper ARIA labels or roles for their actions

  /just had my accesibility course

Acceptance Criteria

• Add proper focus outline styling to verification badge
• Improve aria-label text for verification badge to be more descriptive
• Update pipeline status text to be more specific (e.g., "Pipeline status: failed")
• Tabbing order see #556950 (comment 2644368583) - Moved to #569049 (closed)