Some buttons in editor can´t be accessed using keyboard movement

### Tested versions

- Reproducible in 4.6.1.rc1

### System information

Godot v4.6.1.rc1 - Windows 11 (build 26100) - Multi-window, 1 monitor - OpenGL 3 (Compatibility) - NVIDIA GeForce RTX 3060 Laptop GPU (NVIDIA; 32.0.15.7260) - 12th Gen Intel(R) Core(TM) i7-12700H (20 threads) - 15.79 GiB memory

### Issue description

Some buttons can´t be accessed using the keyboard movement, only by using a mouse can you interact with those

Currently I identified 2 reasons for this:
- The default behaviour of MenuButton, LinkButton, and MenuTabs is set to FOCUS_ACCESSIBILITY
- Buttons spread around the editor have FOCUS_ACCESSIBILITY added to them in editor files

I don´t believe there is any reason that these specific buttons shouldn´t be able to be accessed using a keyboard or controller.

### Steps to reproduce

- Open editor with any project
- Attempt to navigate to buttons like "Extra Scene Options" in the Scene Dock, "Change Split Mode" in the FileSystem dock, "Snapping Options" on the 2D editor using the keyboard

### Minimal reproduction project (MRP)

N/A