Fix array brackets appearing in the wrong place in the snapshot (#56214)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/56214

Changelog: [Internal]

Snapshot generator was putting `[]` in wrong place when generating array type - it was adding it to the type name instead of the variable name. This diff addresses that.

Reviewed By: cipolleschi

Differential Revision: D98102328

fbshipit-source-id: c5b1f290da3c94ad4834a9756d849ae879733033