Bump mongodb from 3.6.4 to 4.0.0

Bumps [mongodb](https://github.com/mongodb/node-mongodb-native) from 3.6.4 to 4.0.0.
- [Release notes](https://github.com/mongodb/node-mongodb-native/releases)
- [Changelog](https://github.com/mongodb/node-mongodb-native/blob/4.0/docs/CHANGES_4.0.0.md)
- [Commits](mongodb/node-mongodb-native@v3.6.4...v4.0.0)

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

package.json

@@ -55,7 +55,7 @@
   "optionalDependencies": {
     "cli-table": "^0.3.4",
     "js-yaml": "^4.0.0",
-    "mongodb": "^3.6.4",
+    "mongodb": "^4.0.0",
     "mongodb-collection-sample": "^4.4.2",
     "mongodb-extended-json": "^1.6.2",
     "mongodb-ns": "^2.0.0",