[desktop] Fix misaligned output device (#2786)

Builder::BuildWidget previously relied on Qt to handle layout stretching
by implicitly setting each widget to have a stretch of 0. This is very
bad behavior, so to fix this we must set a stretch of 1 on each widget
that's added by the builder

furthermore, default and default_dark did not properly define a min-width or min-height for QComboBox. This caused the platform theme to take over sizing which is NOT GOOD and should basically be avoided always

Signed-off-by: crueter <crueter@eden-emu.dev>
Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/2786
Reviewed-by: MaranBr <maranbr@eden-emu.dev>

src/yuzu/configuration/configure_audio.cpp

@@ -126,6 +126,7 @@ void ConfigureAudio::Setup(const ConfigurationShared::Builder& builder) {
                 restore_output_device_button->setVisible(
                     !Settings::values.audio_output_device_id.UsingGlobal());
                 widget->layout()->addWidget(restore_output_device_button);
+
                 connect(restore_output_device_button, &QAbstractButton::clicked, [this](bool) {
                     Settings::values.audio_output_device_id.SetGlobal(true);
                     SetOutputDevicesFromDeviceID();