Remove direct dependency to fluent theme in Core.Presentation.Avalonia

Author: Kryptos-FR

sources/presentation/Stride.Core.Presentation.Avalonia/Stride.Core.Presentation.Avalonia.csproj

@@ -17,7 +17,6 @@
 
   <ItemGroup>
     <PackageReference Include="Avalonia" />
-    <PackageReference Include="Avalonia.Themes.Fluent" />
     <!--Condition below is needed to remove Avalonia.Diagnostics package from build output in Release configuration.-->
     <PackageReference Condition="'$(Configuration)' == 'Debug'" Include="Avalonia.Diagnostics" />
     <PackageReference Include="Markdown.Avalonia.Tight" />

sources/presentation/Stride.Core.Presentation.Avalonia/Windows/CheckedMessageBox.axaml

@@ -12,9 +12,6 @@
         WindowStartupLocation="CenterOwner"
         Padding="8,0" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Center"
         x:Class="Stride.Core.Presentation.Avalonia.Windows.CheckedMessageBox">
-  <Window.Styles>
-    <FluentTheme />
-  </Window.Styles>
   <Window.Resources>
     <ResourceDictionary>
       <ImageBrush x:Key="ImageErrorDialog" Source="/Assets/Images/error-32.png" />

sources/presentation/Stride.Core.Presentation.Avalonia/Windows/MessageBox.axaml

@@ -12,9 +12,6 @@
         WindowStartupLocation="CenterOwner"
         Padding="8,0" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Center"
         x:Class="Stride.Core.Presentation.Avalonia.Windows.MessageBox">
-  <Window.Styles>
-    <FluentTheme />
-  </Window.Styles>
   <Window.Resources>
     <ResourceDictionary>
       <ImageBrush x:Key="ImageErrorDialog" Source="/Assets/Images/error-32.png" />