Support `expand.symint` with real symbolic symint (#3889)
* Add expand.symint
* linter
* addressed some of the comments
* made major change to the code architecture
* linter
* Update ExpandSymintNode
* Add ExpandSymIntSymbolic
* Add ExpandSymIntSymbolic
* Add TestExpandSymIntDynamic
* linter
* Fix review comments
* Update test_aten_xla_tensor.cpp
* update comment
Co-authored-by: JackCaoG <jackcao@google.com>
Co-authored-by: JackCaoG <59073027+JackCaoG@users.noreply.github.com>
