Specify ij indexing when cartesian_prod calls meshgrid (#68753)
Summary:
Currently, `cartesian_prod` calls `meshgrid` without passing an indexing parameter. This causes a warning to be shown when running the `cartesian_prod` example from the docs. This PR simply passes the default value for this indexing parameter instead.
Fixes https://github.com/pytorch/pytorch/issues/68741
Pull Request resolved: https://github.com/pytorch/pytorch/pull/68753
Reviewed By: kimishpatel
Differential Revision: D33173011
Pulled By: mruberry
fbshipit-source-id: 667185ec85bd62bda177bc5768d36f56cfc8b9ab
