UserDefaults to Keychain (wrapper)

[pouriaalmassi]

Description

Swaps out UserDefaults for a keychain wrapper Valet by Square.

Testing Steps

1. Run as a new user.
2. Create a passcode.
3. Attempt to deactivate the passcode.
4. Enter the recently created passcode.

Expected Behaviour

• App should allow you to create a passcode.
• App should allow you to deactivate passcode.
• Data should be written to and read from the Keychain (access provided by the Keychain wrapper).