Missing link in Image Controls info box

[Dragorn421]

https://docs.avaloniaui.net/docs/reference/controls/image-controls aka https://github.com/AvaloniaUI/avalonia-docs/blob/main/docs/reference/controls/image-controls.md currently: https://github.com/AvaloniaUI/avalonia-docs/blob/902e2b09e70474ac82cceacb23a4cbc87f2f3c8b/docs/reference/controls/image-controls.md

has

If you plan to bind an image source, you will need to use an image converter. To learn how to do this, see here.

but there is no link

[MikeCodesDotNET]

Not sure why it was lost, but I think* its likely referring to this.

If you want to make a PR, I'll be happy to review.