Bump mongodb-memory-server from 8.15.1 to 9.0.0

Bumps [mongodb-memory-server](https://github.com/nodkz/mongodb-memory-server/tree/HEAD/packages/mongodb-memory-server) from 8.15.1 to 9.0.0.
- [Release notes](https://github.com/nodkz/mongodb-memory-server/releases)
- [Changelog](https://github.com/nodkz/mongodb-memory-server/blob/master/CHANGELOG.md)
- [Commits](https://github.com/nodkz/mongodb-memory-server/commits/v9.0.0/packages/mongodb-memory-server)

---
updated-dependencies:
- dependency-name: mongodb-memory-server
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

package.json

@@ -35,7 +35,7 @@
     "@types/jest": "^27.0.3",
     "@types/mongoose": "^5.11.96",
     "jest": "^27.4.5",
-    "mongodb-memory-server": "^8.1.0",
+    "mongodb-memory-server": "^9.0.0",
     "mongoose": "^7.0.0",
     "ts-jest": "^27.1.2",
     "tslint": "^5.20.1",