### Godot version

4 beta 10

### System information

win 11

### Issue description

So I have a very skinny tileset image. When I try to make a tile at the top of the image, it jumps down to some where in the middle. Why does it do this?

### Steps to reproduce

make a tileset with a skinny image

### Minimal reproduction project

none
for (const KeyValue<Vector2, HashMap<int, Rect2i>> &E_coords : alternative_tiles_rect_cache) {
		for (const KeyValue<int, Rect2i> &E_alternative : E_coords.value) {
			if (E_alternative.value.has_point(p_pos)) {
				return Vector3i(E_coords.key.x, E_coords.key.y, E_alternative.key);
			}
		}
	}
	return Vector3i(TileSetSource::INVALID_ATLAS_COORDS.x, TileSetSource::INVALID_ATLAS_COORDS.y, TileSetSource::INVALID_TILE_ALTERNATIVE);
}
Rect2i TileAtlasView::get_alternative_tile_rect(const Vector2i p_coords, int p_alternative_tile) {