### 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
bool all_alternatve_id_zero = true;
	for (TileSelection tile : tiles) {
		if (tile.alternative != 0) {
			all_alternatve_id_zero = false;
			break;
		}
	}
	if (all_alternatve_id_zero) {
		Vector<String> components = String(p_name).split("/", true, 2);
		if (p_name == "animation_columns") {
			for (TileSelection tile : tiles) {
				bool has_room_for_tile = tile_set_atlas_source->has_room_for_tile(tile.tile, tile_set_atlas_source->get_tile_size_in_atlas(tile.tile), p_value, tile_set_atlas_source->get_tile_animation_separation(tile.tile), tile_set_atlas_source->get_tile_animation_frames_count(tile.tile), tile.tile);
				if (!has_room_for_tile) {
					ERR_PRINT(vformat("Cannot change the number of columns to %s for tile animation. Not enough room in the atlas to layout %s frame(s).", p_value, tile_set_atlas_source->get_tile_animation_frames_count(tile.tile)));
				} else {
					tile_set_atlas_source->set_tile_animation_columns(tile.tile, p_value);
				}
			}
			emit_signal(SNAME("changed"), "animation_columns");
			return true;
		} else if (p_name == "animation_separation") {
			for (TileSelection tile : tiles) {
				bool has_room_for_tile = tile_set_atlas_source->has_room_for_tile(tile.tile, tile_set_atlas_source->get_tile_size_in_atlas(tile.tile), tile_set_atlas_source->get_tile_animation_columns(tile.tile), p_value, tile_set_atlas_source->get_tile_animation_frames_count(tile.tile), tile.tile);
				if (!has_room_for_tile) {
					ERR_PRINT(vformat("Cannot change separation between frames of the animation to %s. Not enough room in the atlas to layout %s frame(s).", p_value, tile_set_atlas_source->get_tile_animation_frames_count(tile.tile)));
				} else {
					tile_set_atlas_source->set_tile_animation_separation(tile.tile, p_value);
				}
			}
			emit_signal(SNAME("changed"), "animation_separation");