Update examples/rectangle to use typealias keyword.
This corrects one of the problems that were mentioned in
-- Please refer to the LICENSE and AUTHORS files for details
-- SPDX-License-Identifier: MIT
--- The following program demonstrates using table types in Pallene.
+typealias rectangle = { width: float, height: float }
-type rectangle = { width: float, height: float }
-
--- The find_area() function accepts a rectangle object. It evaluates the area
--- and returns it.
function find_area(r: rectangle): float
local result = r.width * r.height
return result
