support Scala 3 build for core module

[xuwei-k]

No description provided.

[andyglow]

Hello, @xuwei-k , thank you for the contribution..
May I ask what this change is for?
If this is a part if a bigger intention, could you show the whole plan?

[xuwei-k]

May I ask what this change is for?

These changes necessary for compile with Scala 3.
Please try sbt '++ 3.1.0!' core/test. I don't know how to add Scala 3 CI settings to .drone.yml sorry.

If this is a part if a bigger intention, could you show the whole plan?

I have no plans yet another modules.(macro migration is hard... 😢 )

[andyglow]

right. macro is completely different
we can get to drone later once macro part is done