Fix compile error on main branch (#1910)

```
In src/lucky/error_action.cr:83:34

 83 | body: Lucky::ExceptionPage.for_runtime_exception(context, error).to_s,
                                 ^--------------------
Error: Error: undefined method 'for_runtime_exception' for Lucky::ExceptionPage.class
```

src/lucky/error_action.cr

@@ -80,7 +80,7 @@ abstract class Lucky::ErrorAction
 
   def render_exception_page(error : Exception, status : Int) : Lucky::Response
     send_text_response(
-      body: Lucky::ExceptionPage.for_runtime_exception(context, error).to_s,
+      body: Lucky::ExceptionPage.new(context, error).to_s,
       content_type: "text/html",
       status: status
     )