[PyTorch] Remove unused sstream/string includes from c10/macros/Macros.h (#83353)
Nothing in the rest of the header seems to use these.
Differential Revision: [D38672680](https://our.internmc.facebook.com/intern/diff/D38672680/)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/83353
Approved by: https://github.com/malfet
