extractors/bilibili: fix regex

[iawia002]

close #183

[codecov]

Codecov Report

Merging #184 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master     #184   +/-   ##
=======================================
  Coverage   82.54%   82.54%           
=======================================
  Files          23       23           
  Lines        1266     1266           
=======================================
  Hits         1045     1045           
  Misses        190      190           
  Partials       31       31

Impacted Files	Coverage Δ
extractors/bilibili/bilibili.go	80.62% <100%> (ø)	⬆️

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