Multi period dash VOD fixes

[dzianis-dashkevich]

Specific Changes proposed

• Clear timeout for media request in dash playlist loader. This fixes the incorrect clearing logic for the media request timeout in the dash playlist loader.
• Add light debounce for fast quality change. This fixes duplicate calls during rapid quality switching. For example, when we select quality from the quality list with multiple bandwidth profiles for the same vertical resolution, it will call for fast quality changes for multiple playlists one by one.
• Add isPaused for the dash playlist loader. This fixes duplicate load calls when mediachange is fired. See this PR for more info https://github.com/videojs/http-streaming/pull/1339)
• Call fast quality change only if a playlist is selected. This fixes duplicate calls when selecting quality from the quality list.
• Ignore duplicate playlist updates in the segment-loader.
• Move fixBadTimelineChanged logic from playlist-controller level to reset all segment-loaders.
• Clear all segment loaders during fast quality change.

Requirements Checklist

• [ ] 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: Patch coverage is 60.86957% with 18 lines in your changes missing coverage. Please review.

Project coverage is 83.97%. Comparing base (2f8d0af) to head (fd15e60). Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/playlist-controller.js	27.27%	16 Missing :warning:
src/dash-playlist-loader.js	80.00%	2 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1551 +/- ## ========================================== - Coverage 84.08% 83.97% -0.11% ========================================== Files 43 44 +1 Lines 11646 11681 +35 Branches 2604 2612 +8 ========================================== + Hits 9792 9809 +17 - Misses 1854 1872 +18 ```

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