Merge pull request #314 from WeiLoy/patch-64

修改下载链接的版本号

Author: biganxin

docs/成为主网验证节点.md

@@ -65,14 +65,14 @@ Ubuntu 18.04：
 
 ```bash
 sudo wget https://download.platon.network/platon/platon/1.4.4/platon -O /usr/bin/platon
-sudo wget https://download.platon.network/platon/platon/1.4.2/platonkey -O /usr/bin/platonkey
+sudo wget https://download.platon.network/platon/platon/1.4.4/platonkey -O /usr/bin/platonkey
 ```
 
 Ubuntu 20.04：
 
 ```bash
 sudo wget https://download.platon.network/platon/platon/ubuntu20.04/1.4.4/platon -O /usr/bin/platon
-sudo wget https://download.platon.network/platon/platon/ubuntu20.04/1.4.2/platonkey -O /usr/bin/platonkey
+sudo wget https://download.platon.network/platon/platon/ubuntu20.04/1.4.4/platonkey -O /usr/bin/platonkey
 ```
 
 Ubuntu 22.04：