populate() broken since 10.0.2

[keen bay]

Hey there,

I found a problem with @nestjs/mongoose since version 10.0.2. When using populate() on an array, mongoose is not populating the array. I think this is a bug in how the Schema is created and I can pinpoint the problem to the change in this PR: https://github.com/nestjs/mongoose/pull/1607. When reverting that change, everything works as expected.

I noticed the issue after upgrading the package beyond 10.0.1 in our code. Unfortunately, I am not very used to reporting bugs and don't really understand the package's code base and would need some help with that.

[keen bay]

I made a reproduction here: https://github.com/schw4rzlicht/nestjs-mongoose-populate-bug