Example 13 error

The line:

```
"url": "http://example.com",
```

should be:

```
"url": "http://example.com/",
```

to match the value in example 12 (which itself comes from example 11)

Compare the URL shown in Example 13 with the values in Examples 11 and 12, as referenced in the issue. Update the Example 13 value to match the established trailing-slash form, then verify the example remains valid and consistent with those preceding examples.

Written by the indexing model from the issue text.