Update parameter type of GetById in POST example (#3446)

Author: InoueKonoha

aspnetcore/includes/webApi/end.md

@@ -37,7 +37,7 @@ You can use the Location header URI to access the resource you just created. Rec
 
 ```csharp
 [HttpGet("{id}", Name = "GetTodo")]
-public IActionResult GetById(string id)
+public IActionResult GetById(long id)
 ```
 
 ### Update
@@ -54,4 +54,4 @@ public IActionResult GetById(string id)
 
 The response is [204 (No Content)](http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html).
 
-![Postman console showing 204 (No Content) response](../../tutorials/first-web-api/_static/pmd.png)
+![Postman console showing 204 (No Content) response](../../tutorials/first-web-api/_static/pmd.png)