'math.randomseed()' sets a somewhat random seed

When called with no arguments, 'math.randomseed' uses time and ASLR
to generate a somewhat random seed. the initial seed when Lua starts
is generated this way.

testes/math.lua

@@ -838,7 +838,7 @@ do
   assert(rand * 2^floatbits == res)
 end
 
-math.randomseed(0, os.time())
+math.randomseed()
 
 do   -- test random for floats
   local randbits = math.min(floatbits, 64)   -- at most 64 random bits