chore(deps): update dependency joi to v18

Author: renovate-bot

package.json

@@ -53,7 +53,7 @@
     "codecov": "^3.6.2",
     "express": "^4.17.1",
     "gts": "^6.0.2",
-    "joi": "^17.0.0",
+    "joi": "^18.0.0",
     "js-green-licenses": "^4.0.0",
     "json-stable-stringify": "^1.3.0",
     "koa": "^3.1.1",