Save cards to Favorites EP

[JonoSommers]

Description:
When a user clicks on a card inside of their binder they will have a button they can select to add to their favorite cards to be displayed at the bottom when they log in. User ID will need to be in the path so that we know which user the favorite is being added to.

Details:

• A user can save 4 cards to their favorites
• A user can remove a card from their favorites
• Favorites can only store up to 4 cards at a time
• A user can only add cards to favorites from their binder
• PATCH request (user id in path)

Examples:
Example request body to add:
(card attribute)

{
    "favorites": true
}

example request body to remove:
(card attribute)

{
    "favorites": false
}

Acceptance Criteria:

• Postman response/request bodies are what we expect
• All tests are passing