Bump mongoose-lean-virtuals from 0.8.1 to 0.9.1

Bumps [mongoose-lean-virtuals](https://github.com/vkarpov15/mongoose-lean-virtuals) from 0.8.1 to 0.9.1.
- [Release notes](https://github.com/vkarpov15/mongoose-lean-virtuals/releases)
- [Changelog](https://github.com/mongoosejs/mongoose-lean-virtuals/blob/master/CHANGELOG.md)
- [Commits](mongoosejs/mongoose-lean-virtuals@0.8.1...0.9.1)

---
updated-dependencies:
- dependency-name: mongoose-lean-virtuals
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

package.json

@@ -79,7 +79,7 @@
     "mongodb": "^3.6.5",
     "mongoose": "^6.5.2",
     "mongoose-lean-defaults": "2.1.0",
-    "mongoose-lean-virtuals": "^0.8.1",
+    "mongoose-lean-virtuals": "^0.9.1",
     "mustache": "^4.1.0",
     "object-hash": "^2.1.1",
     "object-path": "^0.11.5",