fix(deps): update dependency multer to v2 [security]

Author: renovate-bot

bookshelf/package.json

@@ -18,7 +18,7 @@
     "@google-cloud/storage": "^6.0.0",
     "body-parser": "^1.18.3",
     "express": "^4.16.4",
-    "multer": "^1.4.1",
+    "multer": "^2.1.1",
     "pug": "^3.0.0"
   },
   "devDependencies": {