doc(readme): update go version

Signed-off-by: sixhj <sixhj@gmail.com>

README-CN.md

@@ -175,7 +175,7 @@ eKuiper 可以运行在各类物联网的边缘使用场景中，比如工业物
 
 #### 准备
 
-+ Go version >= 1.13
++ Go version >= 1.18
 
 #### 编译
 

README.md

@@ -161,7 +161,7 @@ To run this benchmark by yourself, please check [the instruction](./test/benchma
 
 #### Preparation
 
-- Go version >= 1.13
+- Go version >= 1.18
 
 #### Compile