🤖 src/ghes-releases/lib/enterprise-dates.json update (#57567)

Co-authored-by: heiskr <1221423+heiskr@users.noreply.github.com>
Co-authored-by: Joe Clark <31087804+jc-clark@users.noreply.github.com>

Author: 3 people

src/ghes-releases/lib/enterprise-dates.json

@@ -252,9 +252,9 @@
     "generalAvailabilityDate": "2025-06-03"
   },
   "3.18": {
-    "releaseDate": "2025-08-05",
+    "releaseDate": "2025-09-03",
     "deprecationDate": "2026-08-25",
-    "releaseCandidateDate": "2025-08-05",
+    "releaseCandidateDate": "2025-09-03",
     "generalAvailabilityDate": "2025-10-06"
   },
   "3.19": {