[Static Runtime] Performance optimization for fork operation (#79482)
Summary:
- StaticModule was being created at runtime which was adding overhead to the forked operation
- Move staticModule creation to outside of runtime so that StaticRuntime instance can be created on top of same staticModule that is created once
Differential Revision: D37126923
Pull Request resolved: https://github.com/pytorch/pytorch/pull/79482
Approved by: https://github.com/tenpercent
