feat: enable playlists with 'usable' keystatus

[adrums86]

Description

Only enable playlists with a 'usable' keystatus when playing DASH with DRM.

Specific Changes proposed

Reference the playlist keyId after getting a keystatuschange event from contrib-eme and only enable encrypted playlists that we have a matching usable keyId for.

Note: This PR includes changes from #1461

Requirements Checklist

• [x] Feature implemented / Bug fixed
• [ ] If necessary, more likely in a feature request than a bug fix
  • [ ] Unit Tests updated or fixed
  • [ ] Docs/guides updated
  • [ ] Example created (starter template on JSBin)
• [ ] Reviewed by Two Core Contributors

[codecov[bot]]

Codecov Report

Attention: 1 lines in your changes are missing coverage. Please review.

Comparison is base (c726760) 86.01% compared to head (b6504ea) 86.03%. Report is 1 commits behind head on main.

Files	Patch %	Lines
src/playlist-controller.js	97.14%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1460 +/- ## ========================================== + Coverage 86.01% 86.03% +0.02% ========================================== Files 42 42 Lines 10673 10712 +39 Branches 2456 2462 +6 ========================================== + Hits 9180 9216 +36 - Misses 1493 1496 +3 ```

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[adrums86]

@wseymour15 and @dzianis-dashkevich Thanks for taking a look at this! I just pushed some updates, another look would be appreciated when you have time.