### 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
Rect2i rect = tile_atlas_view->get_alternative_tile_rect(tile_id, alternative_id);
				pos.x = MAX(pos.x, rect.get_end().x);
				y_increment = MAX(y_increment, rect.size.y);
			}
			
			Button *button = memnew(Button);
			alternative_tiles_control->add_child(button);
			button->set_flat(true);
			button->set_icon(get_theme_icon(SNAME("Add"), SNAME("EditorIcons")));
			button->add_theme_style_override("normal", memnew(StyleBoxEmpty));
			button->add_theme_style_override("hover", memnew(StyleBoxEmpty));
			button->add_theme_style_override("focus", memnew(StyleBoxEmpty));
			button->add_theme_style_override("pressed", memnew(StyleBoxEmpty));
			button->connect("pressed", callable_mp(tile_set_atlas_source, &TileSetAtlasSource::create_alternative_tile).bind(tile_id, TileSetSource::INVALID_TILE_ALTERNATIVE));
			button->set_rect(Rect2(Vector2(pos.x, pos.y + (y_increment - texture_region_base_size.y) / 2.0), Vector2(texture_region_base_size_min, texture_region_base_size_min)));
			button->set_expand_icon(true);
			pos.y += y_increment;
		}
	}
	tile_atlas_view->set_padding(Side::SIDE_RIGHT, texture_region_base_size_min);
	
	tile_atlas_control->queue_redraw();
	tile_atlas_control_unscaled->queue_redraw();
	alternative_tiles_control->queue_redraw();
	alternative_tiles_control_unscaled->queue_redraw();
	tile_atlas_view->queue_redraw();
	
	TilesEditorUtils::get_singleton()->synchronize_atlas_view(tile_atlas_view);
}
void TileSetAtlasSourceEditor::_update_toolbar() {