All user saved albums

[edy252]

Title

Adds ability to download and sync tracks from the current user's saved albums on Spotify.

Description

I used the existing current_user_saved_albums function to retrieve the user's saved albums, and added a new CLI argument "get_user_saved_albums". This works with the download and sync operations.

Related Issue

#1940

Motivation and Context

It allows the user to pull their saved albums and download / sync them.

How Has This Been Tested?

I setup the environment using the commands in the contributing page.
I tested these commands:
spotdl all-user-saved-albums --user-auth
spotdl sync all-user-saved-albums --user-auth --save-file sample.spotdl
I checked for these things:

• Download all songs from saved albums on Spotify
• Sync all songs from saved albums on Spotify, skipping items already sync'ed with a spotdl file
• Sync using this command. Then save a new album on Spotify. Run this command. Make sure that already existing songs are skipped, and songs from the newly saved album are downloaded.
• But if after running the sync command, you un-save an album from your Spotify, then the songs belonging to that album are not deleted. Not sure how to proceed with this.
• Run pytest to see that 121/129 existing tests passed (for this branch and for my master branch)

Screenshots (if appropriate)

Types of Changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• My code follows the code style of this project
• My change requires a change to the documentation
• I have updated the documentation accordingly
• I have read the CONTRIBUTING document
• I have read the CORE VALUES document
• I have added tests to cover my changes Not sure how to add a test for this
• All new and existing tests passed Both my branch and my master fail 8 tests