Update dependency debug to v4

Author: renovate-bot

package-lock.json

@@ -11,7 +11,7 @@
     "connect-mongo": "^3.2.0",
     "cookie-parser": "^1.4.5",
     "cors": "^2.8.5",
-    "debug": "~2.6.9",
+    "debug": "4.3.2",
     "dotenv": "^8.2.0",
     "ejs": "^3.1.5",
     "express": "^4.16.4",