Merge pull request #1191 from sw-double/fix-dev-server-docs-typo

Fix dev-server config docs typo

Author: simon04

content/configuration/dev-server.md

@@ -122,7 +122,7 @@ T> `filename` has no effect when used without **lazy mode**.
 
 `object`
 
-Adds headers to all requests:
+Adds headers to all responses:
 
 ```js
 headers: {