Make auto add to up next settings a UserSetting

[mchowning]

Description

This updates the auto add to up next limit and behavior to each be a UserSetting

Testing Instructions

For the Auto Add to Up Next setting, test the "Aut add limit" and "If limit reached" setting by:

1. Fresh install the app
2. Verify that the setting has the same default value that it had before
3. Change the setting to a new value
4. Force close the app
5. Verify that the setting has retained the new value
6. Verify that the app's behavior reflects the updated setting value. Note that you can force new episodes to be received from the "Developer Settings" section by tapping "Delete first episodes" and then tapping "force refresh". When testing whether the up next queue limit be aware that "delete first episodes" will remove items from your queue (i.e., if you set your queue to the max, and then tap delete first episodes, your queue may no longer be at the max).

Checklist

• If this is a user-facing change, I have added an entry in CHANGELOG.md
• Ensure the linter passes (./gradlew spotlessApply to automatically apply formatting/linting)
• I have considered whether it makes sense to add tests for my changes
• All strings that need to be localized are in modules/services/localization/src/main/res/values/strings.xml

[ashiagr]

All tests pass.

Thanks for the extra test details that you include to make testing and reviewing easier.