### Godot version

v4.2.dev3.official [013e8e3af]

### System information

Windows 11, Core i5-12400F, RX 6600

### Issue description

TileSet->Setup->Separation maybe should have "px" like rest?
![Screenshot 2023-08-21 162202](https://github.com/godotengine/godot/assets/962340/3c6b9a97-7520-4610-8153-7882cc9c303f)
I know this is pixels from testing it.

TileSet->Select is this Animation Separation "px" too? idk
![Screenshot 2023-08-21 162131](https://github.com/godotengine/godot/assets/962340/fcb580e3-9ff7-41d8-92d3-e585841d3803)
I tried setting up animation separation and got a not enough room error, so maybe not "px". idk


Thanks.


### Steps to reproduce

- open TileSet->Setup->Separation, note some have "px" and one doesn't
- open TileSet->Select, is this separation "px" too?


### Minimal reproduction project

n/a
#include "tile_set_atlas_source_editor.h"
#include "tiles_editor_plugin.h"
#include "editor/editor_inspector.h"
#include "editor/editor_node.h"
#include "editor/editor_scale.h"
#include "editor/editor_settings.h"
#include "editor/editor_undo_redo_manager.h"
#include "editor/plugins/tiles/tile_set_editor.h"
#include "editor/progress_dialog.h"
#include "scene/gui/box_container.h"
#include "scene/gui/button.h"
#include "scene/gui/control.h"
#include "scene/gui/item_list.h"
#include "scene/gui/separator.h"
#include "scene/gui/split_container.h"
#include "scene/gui/tab_container.h"
#include "core/core_string_names.h"
#include "core/math/geometry_2d.h"
#include "core/os/keyboard.h"
void TileSetAtlasSourceEditor::TileSetAtlasSourceProxyObject::set_id(int p_id) {