Update mongoose to version 6.5.1

Author: depfu[bot]

package-lock.json

@@ -21,7 +21,7 @@
     "jade": "~1.11.0",
     "mocha": "^7.2.0",
     "mockgoose": "^8.0.4",
-    "mongoose": "^5.9.27",
+    "mongoose": "^6.5.1",
     "morgan": "~1.9.1",
     "supertest": "^4.0.2",
     "winston": "^3.2.1",