bump hls.js to v1.6.15

[bluenviron-bot]

No description provided.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 55.57%. Comparing base (14ab95f) to head (5c171a6).
⚠️ Report is 6 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #5216   +/-   ##
=======================================
  Coverage   55.56%   55.57%           
=======================================
  Files         185      185           
  Lines       15510    15510           
=======================================
+ Hits         8618     8619    +1     
+ Misses       6165     6164    -1     
  Partials      727      727           

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[github-actions]

This issue is mentioned in release v1.15.4 🚀
Check out the entire changelog by clicking here