build(java): use actions/github-script v3 tag rather than full semver

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[codecov]

Codecov Report

Merging #265 (2615a49) into master (e0cde0d) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #265   +/-   ##
=========================================
  Coverage     78.13%   78.13%           
  Complexity      172      172           
=========================================
  Files            15       15           
  Lines          1052     1052           
  Branches         83       83           
=========================================
  Hits            822      822           
  Misses          192      192           
  Partials         38       38           

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