Fix some Button selectors

src/Avalonia.Themes.Fluent/Button.xaml

@@ -54,16 +54,16 @@
     <Setter Property="TextBlock.Foreground" Value="{DynamicResource ButtonForegroundPressed}" />
   </Style>
   
-  <Style Selector="Button:disabled">
+  <Style Selector="Button:disabled /template/ ContentPresenter">
     <Setter Property="Background" Value="{DynamicResource ButtonBackgroundDisabled}" />
     <Setter Property="BorderBrush" Value="{DynamicResource ButtonBorderBrushDisabled}" />
     <Setter Property="TextBlock.Foreground" Value="{DynamicResource ButtonForegroundDisabled}" />
   </Style>
 
-  <Style Selector="Button.accent">
-    <Setter Property="Foreground" Value="{DynamicResource AccentButtonForeground}" />
+  <Style Selector="Button.accent /template/ ContentPresenter">
     <Setter Property="Background" Value="{DynamicResource AccentButtonBackground}" />
     <Setter Property="BorderBrush" Value="{DynamicResource AccentButtonBorderBrush}" />
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource AccentButtonForeground}" />
   </Style>
 
   <Style Selector="Button.accent:pointerover /template/ ContentPresenter">
@@ -78,7 +78,7 @@
     <Setter Property="TextBlock.Foreground" Value="{DynamicResource AccentButtonForegroundPressed}" />
   </Style>
 
-  <Style Selector="Button.accent:disabled">
+  <Style Selector="Button.accent:disabled /template/ ContentPresenter">
     <Setter Property="Background" Value="{DynamicResource AccentButtonBackgroundDisabled}" />
     <Setter Property="BorderBrush" Value="{DynamicResource AccentButtonBorderBrushDisabled}" />
     <Setter Property="TextBlock.Foreground" Value="{DynamicResource AccentButtonForegroundDisabled}" />

src/Avalonia.Themes.Fluent/RepeatButton.xaml

@@ -54,7 +54,7 @@
     <Setter Property="TextBlock.Foreground" Value="{DynamicResource RepeatButtonForegroundPressed}" />
   </Style>
 
-  <Style Selector="RepeatButton:disabled">
+  <Style Selector="RepeatButton:disabled /template/ ContentPresenter">
     <Setter Property="Background" Value="{DynamicResource RepeatButtonBackgroundDisabled}" />
     <Setter Property="BorderBrush" Value="{DynamicResource RepeatButtonBorderBrushDisabled}" />
     <Setter Property="TextBlock.Foreground" Value="{DynamicResource RepeatButtonForegroundDisabled}" />

src/Avalonia.Themes.Fluent/ToggleButton.xaml

@@ -40,7 +40,6 @@
     </Setter>
   </Style>
 
-  <!--  PointerOverState  -->
   <Style Selector="ToggleButton:pointerover /template/ ContentPresenter">
     <Setter Property="Background" Value="{DynamicResource ToggleButtonBackgroundPointerOver}" />
     <Setter Property="BorderBrush" Value="{DynamicResource ToggleButtonBorderBrushPointerOver}" />