chore(win): use realtime priority

This will still only set the priority to "High" unless kanata is run in
administrator mode. Otherwise "Realtime" priority would be used.

src/kanata/mod.rs

@@ -297,7 +297,7 @@ impl Kanata {
  log::info!("Asking Windows to increase process priority");
  winapi::um::processthreadsapi::SetPriorityClass(
  winapi::um::processthreadsapi::GetCurrentProcess(),
- winapi::um::winbase::HIGH_PRIORITY_CLASS,
+ winapi::um::winbase::REALTIME_PRIORITY_CLASS,
  );
  }