The text in the toolbar does not follow the font size in the rest of Audacity

### Bug description

Using CachyOS rolling release, Audacity 4 Appimage

As demonstrated in the screenshots below, the items in the toolbar do not follow the rest of Audacity 4's font size

### Steps to reproduce

1. Try to increase or decrease the font size in Preferences -> Appearance -> Appearance -> Body Text Size

### Expected behavior

Font size of the toolbar should change along with the rest of the program

### Actual behavior

It's not changing, and I think it's staying at ~13-14px

### Audacity Version

Audacity 4.0.0

### Operating system

Linux

### Additional context

_No response_

Start in Audacity 4 on Linux and reproduce the issue through Preferences → Appearance → Appearance → Body Text Size. Compare the toolbar with the rest of the application while increasing and decreasing the setting, then trace the toolbar text sizing and make it respond consistently. Done means the toolbar font size changes with Body Text Size, including both increases and decreases.

Written by the indexing model from the issue text.