Create API call to Spotify to add selected DB songs to master playlist - BE - UserStory3d 🐘

[m4ndycheung]

• Send 5 songs via Add Tracks API call (https://developer.spotify.com/documentation/web-api/reference/add-tracks-to-playlist
• Function will take in access token and an array of track ids

Dev Notes:
Items are added in the order they appear in the uris array. For example: {"uris": ["spotify:track:4iV5W9uYEdYUVa79Axb7Rh","spotify:track:1301WleyT98MSxVHPZCA6M"], "position": 3}