docs: update less variables

[liuzaijiang]

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• The commit message follows our guidelines
• Tests for the changes have been added/updated or not needed
• Docs and demo have been added/updated or not needed

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[idux-bot]

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[codecov]

Codecov Report

Merging #988 (af812c7) into main (4db7a81) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #988   +/-   ##
=======================================
  Coverage   92.67%   92.67%           
=======================================
  Files         706      706           
  Lines       69123    69123           
  Branches     8064     8064           
=======================================
  Hits        64058    64058           
  Misses       5065     5065           

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