.zenstack dir is not generated into correct location for pnpm project

[ymc9]

Repro: https://github.com/Azzerty23/zenstack-rest-turbo

Run pnpm zen:up from the root folder, and you'll find .zenstack folder is generated into /@zenstackhq/runtime/node_modules/. The reason is pnpm can install packages locally under other packages. After finding the location of @zenstackhq/runtime package, I think we need to move up two levels to find the real node_modules location.

@jiashengguo

[ymc9]

Fixed by #464