fix: Allocate new slice for each batch in streaming reader (#33359)

Related to #33268

Signed-off-by: Congqi Xia <congqi.xia@zilliz.com>

internal/storage/serde.go

@@ -588,9 +588,8 @@ func (deser *DeserializeReader[T]) Next() error {
 		deser.pos = 0
 		deser.rec = deser.rr.Record()
 
-		if deser.values == nil {
-			deser.values = make([]T, deser.rec.Len())
-		}
+		// allocate new slice preventing overwrite previous batch
+		deser.values = make([]T, deser.rec.Len())
 		if err := deser.deserializer(deser.rec, deser.values); err != nil {
 			return err
 		}