Returns the URIs of a Spotify user's Liked Songs aka Saved Tracks
Spotify track URIs can be used as backups to restore a playlist's contents or copying to a new playlist, or combined with spotify_set_track_uris_as_saved.sh
Spotify track URIs can be used as backups to restore a playlist's contents or copying to a new playlist, or combined with spotify_set_track_uris_to_liked.sh
Requires \$SPOTIFY_ID and \$SPOTIFY_SECRET to be defined in the environment