Palettes expanded/collapsed state not persisted

Issue type

UI bug

Bug description

The state of the palettes (whether they are expanded or collapsed) in the UI does not persist when Musescore is closed, meaning that every time the application is launched, each palette needed to work (or all of them if using the Expand all Palettes option of the Palettes pane) needs to be manually expanded, which is time consuming and frustrating.

Back in Musescore 3.X, it used to be that the state of the palettes would persist between sessions, meaning that the program would reopen with the palettes in the state in which they were left when closed. Either this is a bug in Musescore 4.X, which should be corrected, or this is a wanted behavior, in which case a good middle ground could be to implement a "Palette persistance" option in the parameters to let users choose wether or not they want their palettes state to persist between sessions.

Steps to reproduce

1. Open Musescore and create a new score (or open an existing one)
2. In the Palettes pane options, click on Expand all Palettes
3. Close Musescore
4. Reopen Musescore and reopen the previous score
5. All the palettes are once again collapsed

Screenshots/Screen recordings

No response

MuseScore Version

4.0.2.230651546

Regression

Yes, this used to work in Musescore 3.x and now is broken

Operating system

macOS 10.15.7

Additional context

OS: macOS 10.15
Arch.: x86_64
MuseScore version (64-bit): 4.0.2-230651546
revision: github-musescore-musescore-dbe7c6d