[FR] No icon to add custom image icon

### Bug Description

Cannot find the button to upload a custom image for the workspace icon and drag and drop does not seem to work either

### How to Reproduce

Attempt to find a way to do so

### Expected Behavior

A clear button next to the current icon with the caption on the lines of "Upload an image"

### Operating System

Win11

### AppFlowy Version(s)

0.5.9

### Screenshots

Says "Upload an image..."

### Additional Context

_No response_