update README.md.

Signed-off-by: xiwa <xw2sy@163.com>

README.md

@@ -2,7 +2,7 @@
 
 
 <p align="center">
-<img alt="logo" src="http://www.openiita.com/logo.png">
+<img alt="logo" src="https://www.openiita.com/_nuxt/logo.Dn3SJdkk.png">
 </p>
 <p align="center"><img  src="https://img.shields.io/badge/JDK-11+-important.svg">  <img  src="https://img.shields.io/badge/Redis-5.0-important.svg"> <img  src="https://img.shields.io/badge/SpringBoot-2.6.2-blue.svg"> <img  src="https://img.shields.io/badge/Elasticsearch-7.15.2-red.svg">  <img  src="https://img.shields.io/badge/Satoken-1.30.0-yellow.svg"> 
 </p>