Bump SkiaSharp in /TestUnoIslands/TestUnoIslands.Wpf

Bumps [SkiaSharp](https://github.com/mono/SkiaSharp) from 2.88.3 to 2.88.6.
- [Release notes](https://github.com/mono/SkiaSharp/releases)
- [Commits](mono/SkiaSharp@v2.88.3...v2.88.6)

---
updated-dependencies:
- dependency-name: SkiaSharp
  dependency-type: direct:production
...

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

TestUnoIslands/TestUnoIslands.Wpf/TestUnoIslands.Wpf.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <OutputType>WinExe</OutputType>
@@ -16,7 +16,7 @@
     <PackageReference Include="Uno.WinUI.XamlHost" Version="4.5.14" />
     <PackageReference Include="Uno.WinUI.XamlHost.Skia.Wpf" Version="4.5.14" />
 
-    <PackageReference Include="SkiaSharp" Version="2.88.3" />
+    <PackageReference Include="SkiaSharp" Version="2.88.6" />
     <PackagReference Include="SkiaSharp.Harfbuzz" Version="2.88.3" />
   </ItemGroup>
   <ItemGroup>