Merge pull request #2233 from nestjs/renovate/fastify-4.x

chore(deps): update dependency fastify to v4

Author: kamilmysliwiec

packages/mercurius/package.json

@@ -30,14 +30,14 @@
     "@nestjs/common": "8.4.7",
     "@nestjs/platform-fastify": "8.4.7",
     "@nestjs/testing": "8.4.7",
-    "fastify": "3.29.1",
+    "fastify": "4.2.0",
     "mercurius": "8.12.2",
     "mercurius-integration-testing": "5.0.0"
   },
   "peerDependencies": {
     "@nestjs/common": "^8.2.3",
     "@nestjs/graphql": "^10.0.0",
-    "fastify": "^3.25.0",
+    "fastify": "^3.25.0 || ^4.0.0",
     "mercurius": "^8.12.0 || ^9.0.0"
   }
 }