Accessibility Issues - Preferences

### Bug description

Including multiple accessibility issues into one task for easier.
1. If the User presses 'Tab' key, the first items that should be selected is the first item of the left side menu.
2. Tabbing should scroll Preferences tabs that are scrollable
3. Scrollbars should be persistent in Preferences tabs that are too large
4. (Audio Settings) Make Buffer Length and Latency compensation tabbable
5. (Audio Settings) Default Sample Format is not tabbable
6. (Playback/Recording) Short Skip and Long Skip should be scrollable
7. (General) File button should be tabbable under 'Temporary files location'

### Steps to reproduce

1. Launch Audacity 4
2. Open Preferences
3. Go through the list mentioned above

### Expected behavior

All 7 items should be fixed.

### Actual behavior

_No response_

### Audacity Version

5bfbb6df56731cc8156b740b93cfa2ca9126b223

### Operating system

OS independent

### Additional context

_No response_