chore(docs): update TOC

README.md

@@ -31,7 +31,6 @@ width="800"  height="3">
 
 <!-- START doctoc generated TOC please keep comment here to allow auto update -->
 <!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
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 **目录**
 
 - [前言](#%E5%89%8D%E8%A8%80)