Added FlowDirection override to RadialProgressBar

Author: Avid29

Microsoft.Toolkit.Uwp.UI.Controls.Core/RadialProgressBar/RadialProgressBar.xaml

@@ -8,6 +8,7 @@
         <Setter Property="Outline" Value="{ThemeResource SystemControlBackgroundBaseLowBrush}" />
         <Setter Property="Background" Value="Transparent" />
         <Setter Property="Thickness" Value="4"/>
+        <Setter Property="FlowDirection" Value="LeftToRight"/>
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="local:RadialProgressBar">