Removed a duplicated word in a note. (#11785)

documentation/addons/addons-maven.asciidoc

@@ -280,7 +280,7 @@ It is also useful if you maintain your source code in GitHub or a similar servic
 For production, especially in intranet applications, you should normally use the `local` or `fetch` modes.
 This ensures that separating the availability of the Vaadin CDN service from availability of the application server does not add an extra point of failure.
 
-_They can be be used for production_ if your application is intended as globally available, you want to gain the global delivery benefit of the Vaadin CDN, and the availability tradeoff is not significant.
+_They can be used for production_ if your application is intended as globally available, you want to gain the global delivery benefit of the Vaadin CDN, and the availability tradeoff is not significant.
 ====
 
 === Serving Remotely Compiled Widget Set Locally