Describe the bug
ImageUrl not loaded on Edit page for Category Edit

To Reproduce
Steps to reproduce the behavior:

1. Go to /Admin/Forums
2. Click on Edit some Category
3. Scroll down to Forum Images
4. See any changed

Expected behavior
If I select any image, it will be show here.

System (please complete the following information):

• YAF Version: YAF v4.0.2

Additional context
YAF.Pages.Admin.EditForumModel.cs:250

add this line:
this.Input.ImageURL = forum.ImageURL;