Improved cancellation process and avoidance of infinite loops

[Akeit0]

As long as multi-threaded cancellation is performed, infinite loops can be avoided.

local ret = 0
::loop::
ret = ret + 1
goto loop
return ret

var state = LuaState.Create();
var cancellationTokenSource = new CancellationTokenSource();
cancellationTokenSource.CancelAfter(100);
await state.DoStringAsync(source, "@test.lua", cancellationTokenSource.Token);

Lua.LuaCancelledException : The operation was cancelled during execution on Lua.