docs: update using-a-plugin.md (#1988)

baumannzone · ulivz · commit 1138db48637a · 2019-11-02T15:31:03.000+08:00
Update to use triple `xxx` instead double `xx`, for consistency in all examples
diff --git a/packages/docs/docs/plugin/using-a-plugin.md b/packages/docs/docs/plugin/using-a-plugin.md
@@ -16,7 +16,7 @@ A plugin can be published on npm in `CommonJS` format as `vuepress-plugin-xxx`.
 
 ``` js
 module.exports = {
-  plugins: [ 'vuepress-plugin-xx' ]
+  plugins: [ 'vuepress-plugin-xxx' ]
 }
 ```
 

Original file line number	Diff line number	Diff line change
@@ -16,7 +16,7 @@ A plugin can be published on npm in `CommonJS` format as `vuepress-plugin-xxx`.
`16`	`16`
`17`	`17`	``` js
`18`	`18`	`module.exports = {`
`19`		`- plugins: [ 'vuepress-plugin-xx' ]`
	`19`	`+ plugins: [ 'vuepress-plugin-xxx' ]`
`20`	`20`	`}`
`21`	`21`	```
`22`	`22`