Bump BenchmarkDotNet from 0.15.6 to 0.15.8 (#418)

---
updated-dependencies:
- dependency-name: BenchmarkDotNet
  dependency-version: 0.15.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

src/CommunityToolkit.Maui.Markup.Benchmarks/CommunityToolkit.Maui.Markup.Benchmarks.csproj

@@ -16,7 +16,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="BenchmarkDotNet" Version="0.15.6" />
+    <PackageReference Include="BenchmarkDotNet" Version="0.15.8" />
     <PackageReference Include="BenchmarkDotNet.Diagnostics.Windows" Version="0.14.0" Condition="'$(OS)' == 'Windows_NT'" />
     <PackageReference Include="CommunityToolkit.Mvvm" Version="8.4.0" />
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Workspaces" Version="4.14.0" />