docs(*): fix codecov bad links in README_ZH

[lsytj0413]

Fix the broken codecov status links in README_ZH.md

[codecov-io]

Codecov Report

Merging #6850 into master will increase coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #6850      +/-   ##
==========================================
+ Coverage   41.18%   41.19%   +<.01%     
==========================================
  Files         423      423              
  Lines       58399    58399              
==========================================
+ Hits        24052    24057       +5     
+ Misses      31168    31163       -5     
  Partials     3179     3179

Impacted Files	Coverage Δ
models/gpg_key.go	56.66% <0%> (+0.83%)	⬆️
models/unit.go	67.56% <0%> (+5.4%)	⬆️

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