Update index.en.md

[ouba421]

添加validateFields 第二个参数的英文文档注释

[github-actions]

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.72%. Comparing base (495be63) to head (1d1244c).
⚠️ Report is 48 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #6785   +/-   ##
=======================================
  Coverage   92.72%   92.72%           
=======================================
  Files         335      335           
  Lines        7198     7198           
  Branches     1804     1767   -37     
=======================================
  Hits         6674     6674           
- Misses        489      516   +27     
+ Partials       35        8   -27     

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[zombieJ]

合并到 #6783 里一起？

[Layouwen]

添加validateFields 第二个参数的英文文档注释

如果对于在原 pr 上增加代码不了解.
可以重新提一个新 pr, 一次性把中英文加上.
后面这两个 pr 我这边 close 掉.

或者可以尝试摸索一下