Notebook magic test broken by python 3.12.5 release.

[MarkDaoust]

Description of the bug:

https://docs.python.org/3/whatsnew/changelog.html

gh-121018: Fixed issues where argparse.ArgumentParser.parse_args() did not honor exit_on_error=False. Based on patch by Ben Hsing.

We set exit_on_error=False, but then patch exit to throw a custom exception, catch it, and raise SystemExit (?).

One test is failing, blocking PRs.

Actual vs expected behavior:

Test should pass.

Any other information you'd like to share?

No response