Playlist resource error when playing audio track while downloading

[Uni-verse]

Description:

There have been several use cases where we run into this resource loading error, this one in particular has been happening for a while but can be reproduced easily while opening playlist as audio tracks are being downloaded/saved offline. (at least 2 items in playlist).

Related: https://github.com/brave/brave-ios/issues/4939, https://github.com/brave/brave-ios/issues/5067

Steps to Reproduce

1. Visit website containing audio tracks like digitalbook.io or librivox.org
2. Add 1 item to playlist, allow to download the item
3. Add next item but open playlist and try to play item while its being downloaded
4. Observe

Note: Sometimes, switching between the audio tracks will give the resource error in the playlist.

Actual result: Resource error when playing audio track with 2 or more items in list.

https://user-images.githubusercontent.com/17885425/188930363-16d22965-25d6-46da-8a25-4af11e04cb8e.MP4

Expected result: Audio track should play while being saved

Reproduces how often: [Easily reproduced, Intermittent Issue] almost every time

Brave Version: 1.43 (22.9.2.15)

Device details: iPhone

[srirambv]

Possibly related to/same as #5067