Update dependency BenchmarkDotNet to v0.13.8

Author: renovate[bot]

Benchmarks/Schema.NET.Benchmarks/Schema.NET.Benchmarks.csproj

@@ -11,7 +11,7 @@
   </ItemGroup>
 
   <ItemGroup Label="Package References">
-    <PackageReference Include="BenchmarkDotNet" Version="0.13.5" />
+    <PackageReference Include="BenchmarkDotNet" Version="0.13.8" />
   </ItemGroup>
 
 </Project>