consider Sequence[Any] instead of Iterable[Any] for ChoiceFields choices

[asottile-sentry]

this isn't a bug but perhaps a suggestion.

when rest_framework's ChoiceField and MultipleChoiceField receive an unordered collection for choices it can lead to a negative experience: unordered form output, unordered schema, etc.

djangorestframework-stubs/rest_framework-stubs/fields.pyi

Line 460 in e0e9e1f

choices: Iterable[Any],

we've made a small plugin for sentry that enforces this for our uses since we kept hitting this problem: getsentry/sentry#53707

though this isn't entirely in spirit of the type system so understandable if this isn't a good idea