### 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
ERR_FAIL_COND(!p_tile_set_atlas_source.is_valid());
	ERR_FAIL_COND(p_tiles.is_empty());
	for (const TileSelection &E : p_tiles) {
		ERR_FAIL_COND(E.tile == TileSetSource::INVALID_ATLAS_COORDS);
		ERR_FAIL_COND(E.alternative < 0);
	}
	
	for (const TileSelection &E : tiles) {
		const Vector2i &coords = E.tile;
		const int &alternative = E.alternative;
		if (tile_set_atlas_source.is_valid() && tile_set_atlas_source->has_tile(coords) && tile_set_atlas_source->has_alternative_tile(coords, alternative)) {
			TileData *tile_data = tile_set_atlas_source->get_tile_data(coords, alternative);
			if (tile_data->is_connected(CoreStringNames::get_singleton()->property_list_changed, callable_mp((Object *)this, &Object::notify_property_list_changed))) {
				tile_data->disconnect(CoreStringNames::get_singleton()->property_list_changed, callable_mp((Object *)this, &Object::notify_property_list_changed));
			}
		}
	}
	tile_set_atlas_source = p_tile_set_atlas_source;
	tiles = RBSet<TileSelection>(p_tiles);
	
	for (const TileSelection &E : p_tiles) {