Bump npm from 6.13.7 to 6.14.6

Bumps [npm](https://github.com/npm/cli) from 6.13.7 to 6.14.6.
- [Release notes](https://github.com/npm/cli/releases)
- [Changelog](https://github.com/npm/cli/blob/v6.14.6/CHANGELOG.md)
- [Commits](npm/cli@v6.13.7...v6.14.6)

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -36,7 +36,7 @@
     "mongoose-unique-validator": "^2.0.3",
     "multer": "^1.4.2",
     "node": "^8.10.0",
-    "npm": "^6.13.4",
+    "npm": "^6.14.6",
     "require-dir": "^1.2.0",
     "socket.io": "^2.4.0",
     "update-notifier": "^3.0.1",