`update-set` should accept multiple set deltas

[yaakov-stein]

Currently, if you want to update multiple sets, you can either call update-set multiple times or use the chain update/set operations. A better option would be passing multiple set deltas via the update-set operation.

[ty239]

Could I work on this?

[qdeslandes]

Could I work on this?

Sure, assigning the issue to you. Let me know if you'd like direction :)