add explicit override for Address.hashCode

[macfarla]

PR description

Looking through history, equals was added in #8013 so I don't think this class ever had a hashCode implementation.

Fixed Issue(s)

This fixes (several) warnings in CodeQL, since Address class defines equals() but not hashCode(), and is used in hashing data structures. Think this functionally has no effect and no performance impact since it is just delegating to the superclass.

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