Remove double "the"

docs/guide/rest-response-formatting.md

@@ -15,7 +15,7 @@ with response formatting:
 
 ## Content Negotiation <a name="content-negotiation"></a>
 
-Yii supports content negotiation via the [[yii\filters\ContentNegotiator]] filter. The the RESTful API base
+Yii supports content negotiation via the [[yii\filters\ContentNegotiator]] filter. The RESTful API base
 controller class [[yii\rest\Controller]] is equipped with this filter under the name of `contentNegotiator`.
 The filer provides response format negotiation as well as language negotiation. For example, if a RESTful
 API request contains the following header,