Fix type mismatch

msys2 was reporting the following error:
```
D:/a/qbittorent_msys2/qbittorent_msys2/src/qBittorrent/src/app/application.cpp: In member function 'void Application::applyMemoryWorkingSetLimit()':
D:/a/qbittorent_msys2/qbittorent_msys2/src/qBittorrent/src/app/application.cpp:777:36: error: no matching function for call to 'min(unsigned int, long unsigned int)'
  777 |     const SIZE_T minSize = std::min((64 * MiB), (maxSize / 2));
      |                            ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
```

src/app/application.cpp

@@ -774,7 +774,7 @@ void Application::applyMemoryWorkingSetLimit()
 
 #ifdef Q_OS_WIN
     const SIZE_T maxSize = memoryWorkingSetLimit() * MiB;
-    const SIZE_T minSize = std::min((64 * MiB), (maxSize / 2));
+    const auto minSize = std::min<SIZE_T>((64 * MiB), (maxSize / 2));
     if (!::SetProcessWorkingSetSizeEx(::GetCurrentProcess(), minSize, maxSize, QUOTA_LIMITS_HARDWS_MAX_ENABLE))
     {
         const DWORD errorCode = ::GetLastError();