fix:proper sponsorship dates

Author: anyulled

src/data/2025.json

@@ -30,7 +30,7 @@
   "showInfoButtons": false,
   "sponsors": {
     "startDate": "2024-01-01T09:00:00+01:00",
-    "endDate": "2025-06-09T09:00:00+01:00"
+    "endDate": "2025-07-11T09:00:00+01:00"
   },
   "startDay": "2025-07-08T09:00:00+01:00",
   "tickets": {