feat: Extend `get_feature_view` to return stream and on demand feature views by tokoko · Pull Request #4328 · feast-dev/feast

That's mostly to accommodate the linter for now, I should probably add more feast-specific exceptions (for example if a user is asking to materialize an odfv, which doesn't make sense)

On a general note, I found that we have a following trade-off here:

• When get_feature_view returns all types a lot of most common operations become cleaner to implement, for example when a user is passing a list of fv names that might be any one of them, we no longer need crazy exception handling to figure out which method to call.
• In some other less common cases when only a single fv type makes sense, we will now have to check the type of the object returned, we can no longer rely on the fact that registry method used would do that for us. When we drop py3.9, we should probably start using python match statements for this.

Despite the trade-off, I still think it's a worthwhile change. Still wanted to get your opinion.