Add Equals to JWKSet

[Victor Herraiz]

This is really useful in some tests

[Vladimir Dzhuvinov]

Already present:

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (!(o instanceof JWKSet)) return false;
        JWKSet jwkSet = (JWKSet) o;
        return getKeys().equals(jwkSet.getKeys()) && customMembers.equals(jwkSet.customMembers);
    }

[Vladimir Dzhuvinov]

PS: It might have been added in some PR after you filed this ticket.