update benchmarks

Author: twsouthwick

.github/workflows/benchmarks.yml

@@ -28,7 +28,7 @@ jobs:
         run: cd test/DocumentFormat.OpenXml.Benchmarks; dotnet build -c RELEASE
         shell: pwsh
       - name: Run benchmarks
-        run: cd test/DocumentFormat.OpenXml.Benchmarks; dotnet run -c RELEASE -f net8.0
+        run: cd test/DocumentFormat.OpenXml.Benchmarks; dotnet run -c RELEASE -f net10.0
         shell: pwsh
       - name: Write summary
         shell: pwsh