test: de-flake internal/metrics timing-sensitive tests - #788

Bugbot Analysis Progress (4m 7s elapsed)

✅ Gathered PR context (3s)
✅ Completed bug detection (4m 2s)
✅ Posted analysis results (2s)

Final Result: Bugbot completed review - no issues found! ✅

Request ID: serverGenReqId_aa5f9574-b11b-431d-9cfb-1e755987f46d