Remove try/catch in constant propagation (#19686)
Summary:
Stack from [ghstack](https://github.com/ezyang/ghstack):
* **#19686 [jit] Remove try/catch in constant propagation**
The try-catch here gets tripped pretty often when constant prop is run which screws up `catch throw` in gdb.](https://our.intern.facebook.com/intern/diff/15170134/)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/19686
Pulled By: driazati
Differential Revision: D15170134
fbshipit-source-id: 93688561126f3ab582c8358e8f2787f7fce9aa73
