dynamic_shapes + retrace exported program (#110276)
An `ExportedProgram`'s `__call__` signature is different from the original module, so `dynamic_shapes` that follow the original signature would fail when applied to re-export an `ExportedProgram`.
This PR fixes this issue, in other words, the original `dynamic_shapes` should now work when re-exporting.
Differential Revision: D49764011
Pull Request resolved: https://github.com/pytorch/pytorch/pull/110276
Approved by: https://github.com/tugsbayasgalan
