[native] Fix broken StyleProps type for react-native-reanimated libdef

Summary:
This issue was first introduced in D5556, and led to a $FlowFixMe being introduced in D13066.

It's not possible to spread a non-object. I remove the spreads here because the only relevant part of the union is the object form ({ [name: string]: any, ... }), which is already included in the StyleProps type anyways.

This diff addresses part of ENG-9039.

Test Plan: Flow

Reviewers: inka, tomek

Reviewed By: inka

Differential Revision: https://phab.comm.dev/D13124