fix(llhls): watcher causes playback failure

[adrums86]

Description

Low latency streams can get into a bad state on startup and fail if the seek position is adjusted with the playback watcher, specifically by fixesBadSeeks. There are checks in that function that determine if a seek position is outside the seekable window. This seekable range is a calculated interval duration from the playlist, where the end of the seekable window is the duration - HOLD-BACK. When the player first calculates the seekable range from the manifest, the interval duration returned is not precise. Sometimes this non-precise duration will be greater than the precise duration determined after the playlist is loaded. Since the player uses the first, non-precise duration calculation to determine the start position of a live asset, if the precise duration is updated to a lesser value before the player completes the seek to the start position this can cause the start position to fall outside of the "safe seek window". When combined with a manifest that utilizes #EXT-X-INDEPENDENT-SEGMENTS tags, this would cause the player to get stuck requesting the same partial segment in rapid succession, triggering playlist exclusion logic and eventual a fatal MEDIA_ERR_DECODE.

The PRs for #EXT-X-INDEPENDENT-SEGMENTS support are:
videojs/m3u8-parser#165
and
#1399

Specific Changes proposed

Adding an exclusion for LLHLS to allow for seeking beyond the "safe" seek window.

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]

Codecov Report

❗ No coverage uploaded for pull request base (main@f9a392f). Click here to learn what that means.
The diff coverage is 100.00%.

❗ Current head 4abadab differs from pull request most recent head 6c7eeae. Consider uploading reports for the commit 6c7eeae to get more accurate results

@@           Coverage Diff           @@
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Impacted Files	Coverage Δ
src/playback-watcher.js	98.34% <100.00%> (ø)

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