[Profiler] record gradient from nnModule (#86355)
Summary:
- catch .grad tensor info
- update data type and `check_and_store`, etc
- update unit test case
Test Plan: buck run mode/opt //caffe2/test:profiler
Reviewed By: chaekit
Differential Revision: D39711295
Pull Request resolved: https://github.com/pytorch/pytorch/pull/86355
Approved by: https://github.com/chaekit
