BUG: integrate: expose ODEintWarning

[j-bowhay]

Reference issue

closes #17771

What does this implement/fix?

ODEintWarning is not currently exposed in the scpy.integrate namespace which means it is not possible to filter ODEintWarning during the execution of odeint without importing it from the deprecated scipy.integrate.odepack namespace. It was suggested by @WarrenWeckesser that this should be exposed in the integrate namespace.

Additional information

[mdhaber]

This looks fine to me, but since it is about the old odeint API, I can see arguments for leaving it out and marking gh-17771 as wontfix. Since it's about a new public feature, better ask the mailing list.

[j-bowhay]

Email sent. There did seem to be support for exposing ODEintWarning in the original issue from @WarrenWeckesser

Sorry this issue dropped off my radar. I'd say, if we create a custom warning and raise it in public functions--so users will be exposed to that warning--then the warning itself should also be available as part of the public API. So I think we should update the API so that from scipy.integrate import ODEintWarning works. This would be consistent with other warnings that are currently in public namespaces, such as scipy.integrate.IntegrationWarning, scipy.stats.ConstantInputWarning, scipy.optimize.OptimizationWarning, etc.

[rgommers]

LGTM, I think this is fine to expose.

[rgommers]

A few folks are in favor and no one saw an issue (no answers to the mailing list message), so in it goes. Thanks Jake & all