Fix: Handle missing files in MinIO storage by catching Exception in get_attrs

[ashkov]

Problem

When using MinIO/S3 storage, if an image file is deleted from storage,
the admin interface crashes with NoSuchKey exception because
get_attrs() doesn't handle missing files properly.

Solution

Add Exception handling in get_attrs() function to catch cases when
image file doesn't exist in storage.

Changes

• Modified image_cropping/widgets.py
• Added try/except block around image.width and image.height access