Update dependency @sinonjs/fake-timers to v15 (#11942)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

package.json

@@ -77,7 +77,7 @@
     "@percy/ember": "5.0.0",
     "@percy/playwright": "1.0.9",
     "@playwright/test": "1.55.0",
-    "@sinonjs/fake-timers": "14.0.0",
+    "@sinonjs/fake-timers": "15.0.0",
     "@types/node": "22.18.5",
     "@types/sinonjs__fake-timers": "8.1.5",
     "@zestia/ember-auto-focus": "5.1.0",