numeric suite: add types to eager (#51168)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/51168
Adds types to function I/O for numeric suite. This is for readability
and static type checking with mypy.
Test Plan:
```
mypy torch/quantization/
```
Imported from OSS
Reviewed By: jerryzh168
Differential Revision: D26092454
fbshipit-source-id: d37cf61e4d9604f4bc550b392f55fb59165f7624
