[custom_op] Change the python type that maps to ListType in schema (#101190)
Previously, to specify e.g. int[], a user needed to do Tuple[int, ...].
This PR changes it to Sequence[int].
Bikeshedding: we could totally just use List[int] instead. The types
that the user gives us that we use to infer a schema is not entirely
faithful: for example, we convert `int` to SymInt.
I didn't feel strongly between Sequence[int] and List[int] so I went
with the more faithful one, plus Python recommends that you use Sequence
for input arguments (over list or tuple), though we don't subscribe to
that philosophy in general.
Test Plan:
- new test
Pull Request resolved: https://github.com/pytorch/pytorch/pull/101190
Approved by: https://github.com/bdhirsh
