Dear Calcite Maintainers, I have come across the following line of code <https://github.com/apache/calcite/blob/2bdc6af448693c81da3e16208b1af2325fee1d2a/core/src/main/java/org/apache/calcite/jdbc/JavaTypeFactoryImpl.java#L259> which basically treats any java set as list. Is there a specific reason for this? I would like to propose to use a different abstraction, namely `Collection`. Curious of what you think.
Best regards, Andrew Mereuta
