fix: type define of compress.ts

[hovenjay]

fix #497

[codecov]

Codecov Report

Merging #498 (a942151) into master (2d474dc) will not change coverage.
The diff coverage is n/a.

❗ Current head a942151 differs from pull request most recent head 81aa67b. Consider uploading reports for the commit 81aa67b to get more accurate results

@@           Coverage Diff           @@
##           master     #498   +/-   ##
=======================================
  Coverage   40.00%   40.00%           
=======================================
  Files           7        7           
  Lines         455      455           
  Branches       99       99           
=======================================
  Hits          182      182           
  Misses        271      271           
  Partials        2        2           

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[yinxulai]

仔细看了一下，是类型写的不对，确实可能返回 File