feat: Add converter for aten::isfinite

[mfeliz-cruise]

Description

Adds a converter to support aten::isfinite https://pytorch.org/docs/stable/generated/torch.isfinite.html.

Implemented as (x-x)==(x-x). Relies on the fact that x-x = NaN for NaN, inf and -inf and NaN != NaN.

Fixes # (issue)

Type of change

Please delete options that are not relevant and/or add your own.

• New feature (non-breaking change which adds functionality)

Checklist:

• My code follows the style guidelines of this project (You can use the linters)
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas and hacks
• I have made corresponding changes to the documentation
• I have added tests to verify my fix or my feature
• New and existing unit tests pass locally with my changes
• I have added the relevant labels to my PR in so that relevant reviewers are notified

[peri044]

@narendasan can you merge this ? I still don't have permissions.