Brush Tool cursor size is not the same as the stroke size

[newzealandpaul]

Describe the bug

When selecting a brush and adjusting the size of the brush, the cursor (a circle) does not change size to reflect the brush size.

To Reproduce

1. Select the default image segmentation template.
2. Try using the brush tool on the airplanes.
3. Adjust the size of the brush and try zooming in and out.
4. The size of the brush cursor does not match the size of the brush, making it very hard to do pixel-perfect brusing.

Expected behavior
The size of the cursor matches the size of the brush.

Screenshots

In this screenshot, the cursor is white and the green annotation is the size of the brush.

Environment (please complete the following information):

• OS: Linux
• Label Studio Version v1.5.0

[makseq]

Related: #1247 (comment)