Regressed in https://github.com/ppy/osu/pull/28399.
To reproduce, enter a playlist that has an item with a rate-changing mod
(rather than create it yourself).
This is happening because `APIRuleset` has `CreateInstance()`
unimplemented:
https://github.com/ppy/osu/blob/b4cefe0cc2fda0ab4b5af6138ee158bd32262f9a/osu.Game/Online/API/Requests/Responses/APIBeatmap.cs#L159
and only triggers when the playlist items in question originate from
web.
This is why it is bad to have interface implementations throw outside of
maybe mock implementations for tests. `CreateInstance()` is a scourge
elsewhere in general, we need way less of it in the codebase (because
while convenient, it's also problematic to implement in online contexts,
and also expensive because reflection).