commutativeUnion<T> static method
Verifies the Commutative Law for Union.
Law: A ∪ B = B ∪ A
The order of sets in a union operation does not matter.
Implementation
static bool commutativeUnion<T>(CustomSet<T> a, CustomSet<T> b) =>
SetOperations.union(a, b).equals(SetOperations.union(b, a));