[qt] fix configure_debug; use a better method of getting multiple setting values (#4092)

uses `QString::number(Settings::values.serial_battery.GetValue())` instead of `QString::fromStdString(std::to_string(Settings::values.serial_battery.GetValue())));` on two different setting options

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4092
Reviewed-by: Lizzie <lizzie@eden-emu.dev>
Reviewed-by: Shinmegumi <shinmegumi@eden-emu.dev>

src/yuzu/configuration/configure_debug.cpp

@@ -52,9 +52,11 @@ void ConfigureDebug::SetConfiguration() {
     ui->extended_logging->setChecked(Settings::values.extended_logging.GetValue());
     ui->perform_vulkan_check->setChecked(Settings::values.perform_vulkan_check.GetValue());
     ui->serial_battery_edit->setText(
-        QString::fromStdString(std::to_string(Settings::values.serial_battery.GetValue())));
+        QString::number(Settings::values.serial_battery.GetValue())
+    );
     ui->serial_board_edit->setText(
-        QString::fromStdString(std::to_string(Settings::values.serial_unit.GetValue())));
+        QString::number(Settings::values.serial_unit.GetValue())
+    );
 #ifdef YUZU_USE_QT_WEB_ENGINE
     ui->disable_web_applet->setChecked(Settings::values.disable_web_applet.GetValue());
 #else