Merge pull request OAI#1400 from taxpon/fix-typo-in-example

fix typo

Author: Ron

examples/v2.0/yaml/petstore.yaml

@@ -28,7 +28,7 @@ paths:
           format: int32
       responses:
         "200":
-          description: An paged array of pets
+          description: A paged array of pets
           headers:
             x-next:
               type: string