[Woo POS] Improve card reader software update image

[joshheald]

Description

The card reader software updates progress indicator is made of a series of (generated?) images, shown as an animation.

When presented in SwiftUI, this leads to the image pulsing irregularly when it's updated. (There may be another cause, e.g. the redrawing.)

The images also use the old purple, and are shown at 1x so blurry.

software.update.mp4

[dangermattic]

🚫 Please add a type label (e.g. type: enhancement) and a feature label (e.g. feature: stats) to this issue.