Team2 [1.5pt] Implement methods - MusicAlbum and Genre class

[adamteddychang]

Implement methods: add_item method in the Genre class

• should take an instance of the Item class as an input
• should add the input item to the collection of items
• should add self as a property of the item object (by using the correct setter from the item object)

can_be_archived?() in the MusicAlbum class

• should override the method from the parent class
• should return true if parent's method returns true AND if on_spotify equals true
• otherwise, it should return false