Equality and Hashcode differ for Sets with different order

[Michael Lamers]

Describe the bug
For properties of type Set the result of hashCode is unexpected.
Equality works like expected (order of Set elements doesn't have an impact) but hashCode produces different values depending on the order in the Set.

To Reproduce
Steps to reproduce the behavior:

import 'package:equatable/equatable.dart';

class EquatableWithSet extends Equatable {
  final Set<int> intSet;

  EquatableWithSet(this.intSet);

  @override
  List<Object?> get props => [
        intSet,
      ];
}

void main(List<String> arguments) {
  final obj1 = EquatableWithSet({1,2,3});
  final obj2 = EquatableWithSet({3,1,2});

  assert(obj1 == obj2, 'Are not equal!');
  assert(obj1.hashCode == obj2.hashCode, 'Don\'t have the same hashcode!');
}

Expected behavior
Two objects that are equal also have the same hashCode (independent of the order in the Set)

Screenshots
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Version
Dart SDK version: 2.17.5 (stable) (Tue Jun 21 11:05:10 2022 +0200) on "macos_x64"

Additional context
Add any other context about the problem here.