fix: use xhr instead of the fetch api

[xiaoyuhen]

fix: use xhr instead of the fetch api

Description

AbortController only support Chrome 66+, so we use xhr instead of the fetch api.

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 #56 into master will decrease coverage by 0.28%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master      #56      +/-   ##
==========================================
- Coverage   52.86%   52.57%   -0.29%     
==========================================
  Files         123      123              
  Lines        1678     1687       +9     
==========================================
  Hits          887      887              
- Misses        791      800       +9

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

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