fix(deps): update dependency diff to v8 [security]

Author: renovate[bot]

package.json

@@ -25,7 +25,7 @@
     "@prisma/client": "6.19.0",
     "@tryghost/admin-api": "1.14.2",
     "deepl-node": "1.22.0",
-    "diff": "7.0.0",
+    "diff": "8.0.3",
     "discord.js": "14.19.3",
     "dotenv": "16.6.1",
     "fastify": "5.7.3",