chore: make node 18 support never end (for test purposes) (#537)

make node 18 support never end

Author: lerouxb

packages/sbom-tools/test/fixtures/nodejs-schedule.json

@@ -99,7 +99,7 @@
     "start": "2022-04-19",
     "lts": "2022-10-25",
     "maintenance": "2023-10-18",
-    "end": "2025-04-30",
+    "end": "2050-04-30",
     "codename": "Hydrogen"
   },
   "v19": {