[0.5pt] Implement all methods of Item class (Group Task)

[Zuhaib042]

• Implement methods:
  • can_be_archived?() in the Item class
    • should return true if published_date is older than 10 years
    • otherwise, it should return false
  • move_to_archive() in the Item class
    • should reuse can_be_archived?() method
    • should change the archived property to true if the result of the can_be_archived?() method is true
    • should do nothing if the result of the can_be_archived?() method is false