public void SpeedBoostCanBeInstantiatedWithCustomDuration()
        {
            SpeedBoost powerup = new SpeedBoost(20f);

            Assert.AreEqual(20f, powerup.Duration());
        }
        public void SpeedBoostCanBeInstantiatedWithNullDuration()
        {
            SpeedBoost powerup = new SpeedBoost(null);

            Assert.AreEqual(null, powerup.Duration());
        }
        public void SpeedBoostCanBeInstantiated()
        {
            SpeedBoost powerup = new SpeedBoost();

            Assert.AreEqual(10f, powerup.Duration());
        }