Don't wrap event errors

Author: JordonPhillips

packages/aws-event-stream/src/aws_event_stream/_private/deserializers.py

@@ -50,7 +50,9 @@ async def receive(self) -> E | None:
             event = await Event.decode_async(self._source)
         except Exception as e:
             await self.close()
-            raise IOError("Failed to read from stream.") from e
+            if not isinstance(e, EventError):
+                raise IOError("Failed to read from stream.") from e
+            raise
 
         if event is None:
             return None