[lua] Add Uuid tests

Missing file from 636cce6f0d commit

tests/scripts/uuid.lua

@@ -0,0 +1,26 @@
+-- Copyright (C) 2023  Igara Studio S.A.
+--
+-- This file is released under the terms of the MIT license.
+-- Read LICENSE.txt for more information.
+
+local a = Uuid()
+local b = a
+assert(a == b)
+assert(a ~= Uuid())
+
+local s = tostring(a) -- e.g. "74341b56-4f7f-4ab1-9495-58cf5bce0e1c"
+assert(a == Uuid(s))  -- Check that Uuid(string) is working
+assert(#s == 36)
+
+-- Test __index
+local t = string.format("%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
+                        a[1], a[2], a[3], a[4],
+                        a[5], a[6],
+                        a[7], a[8],
+                        a[9], a[10],
+                        a[11], a[12], a[13], a[14], a[15], a[16])
+assert(s == t)
+
+-- Out of bounds
+assert(nil == a[0])
+assert(nil == a[17])