Bump Avalonia and Avalonia.Desktop

Bumps Avalonia from 11.3.8 to 11.3.9
Bumps Avalonia.Desktop from 11.3.8 to 11.3.9

---
updated-dependencies:
- dependency-name: Avalonia
  dependency-version: 11.3.9
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: Avalonia.Desktop
  dependency-version: 11.3.9
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

ImageMerge/ImageMerge.csproj

@@ -10,8 +10,8 @@
     </PropertyGroup>
 
     <ItemGroup>
-        <PackageReference Include="Avalonia" Version="11.3.8"/>
-        <PackageReference Include="Avalonia.Desktop" Version="11.3.8"/>
+        <PackageReference Include="Avalonia" Version="11.3.9"/>
+        <PackageReference Include="Avalonia.Desktop" Version="11.3.9"/>
         <PackageReference Include="Avalonia.Themes.Fluent" Version="11.3.8"/>
         <PackageReference Include="Avalonia.Fonts.Inter" Version="11.3.8"/>
         <!--Condition below is needed to remove Avalonia.Diagnostics package from build output in Release configuration.-->