extractors/youtube: download by range to bypass throttling

[iawia002]

close #191

[codecov]

Codecov Report

Merging #192 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master     #192   +/-   ##
=======================================
  Coverage   86.83%   86.83%           
=======================================
  Files          23       23           
  Lines        1276     1276           
=======================================
  Hits         1108     1108           
  Misses        137      137           
  Partials       31       31

Impacted Files	Coverage Δ
extractors/youtube/signature.go	83.33% <ø> (ø)	⬆️
extractors/youtube/youtube.go	92.85% <100%> (ø)	⬆️

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