fix: end of stream when last GOP is played

[xiaoyuhen]

fix: end of the stream when last GOP is played

Description

if we end of steam when the last GOP is not playing, the video duration will be changed, and the last GOP will not play ever.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules

[codecov-io]

Codecov Report

Merging #83 into master will not change coverage.
The diff coverage is 0%.

@@           Coverage Diff           @@
##           master      #83   +/-   ##
=======================================
  Coverage   50.59%   50.59%           
=======================================
  Files         124      124           
  Lines        1753     1753           
=======================================
  Hits          887      887           
  Misses        866      866

Impacted Files	Coverage Δ
packages/griffith-mp4/src/mse/controller.js	0% <0%> (ø)	⬆️

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