chore(deps): update dependency fastify to v3.21.0

Author: renovate-bot

package-lock.json

@@ -34,7 +34,7 @@
     "reflect-metadata": "0.1.13",
     "rxjs": "7.3.0",
     "express": "4.17.1",
-    "fastify": "3.20.2",
+    "fastify": "3.21.0",
     "fastify-static": "4.2.3",
     "husky": "7.0.2",
     "lint-staged": "11.1.2",