Arithmetic lint does not play nicely with stable

[AaronFeickert]

The linting CI is currently broken due to two recent merges not playing nicely together. Specifically, #113 moves CI to stable, and #118 adds an arithmetic lint. The lint requires an exception in its configuration to avoid false positives, but this doesn't work on stable. The two changes were never tested in CI together, so this wasn't caught prior to merging.

One fix is to remove the lint. The other is to move the linting CI to nightly, noting (as in #112) that moving beyond nightly-2024-02-04 will break due to an incompatibility with the curve library.

[AaronFeickert]

This only appears to arise in the work-in-progress #94, which updates the curve library. Closing since it's not directly relevant to the current codebase.