Fixes for README_ZH

[jolheiser]

Related to #7505

I'm not sure how much the Chinese readme file is used, but I don't want to leave broken images on a living document if possible.

While I was in there, I changed the Discord URLs to the new one as well.

[codecov-io]

Codecov Report

Merging #7506 into master will decrease coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #7506      +/-   ##
==========================================
- Coverage   41.23%   41.23%   -0.01%     
==========================================
  Files         469      469              
  Lines       63602    63602              
==========================================
- Hits        26227    26225       -2     
- Misses      33954    33956       +2     
  Partials     3421     3421

Impacted Files	Coverage Δ
modules/log/event.go	64.61% <0%> (-1.03%)	⬇️

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