[2pt] - Create MusicAlbum class

[laiifuu]

• Create MusicAlbum class in a separate .rb file.
• All MusicAlbum class properties visible in the diagram should be defined and set up in the constructor method.
• 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