LotAtc: infinite update loop and WinError 5 (Access Denied) in schedule()

[luisrdm1]

schedule() compares the latest available version against self.version (the instance DLL) but never calls update_instance() to copy the updated files across. Since the instance version never changes, the condition stays True every 30 minutes → infinite update loop.

A second problem: if update_instance() is called while LotAtc is running, uninstall() fails with WinError 5 (Access Denied) because it tries to delete the loaded DLL:

ERROR  LotAtc update failed: [WinError 5] Access Denied:
       '...\Mods\services\LotAtc\bin\plugins\sqldrivers\qsqlitelotatc.dll'

I have a fix ready and can submit a PR if you'd like.