Bump xunit.extensibility.execution from 2.5.3 to 2.6.4 in /src (#2748)

Bumps [xunit.extensibility.execution](https://github.com/xunit/xunit) from 2.5.3 to 2.6.4.
- [Commits](xunit/xunit@2.5.3...2.6.4)

---
updated-dependencies:
- dependency-name: xunit.extensibility.execution
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

src/IoTHub.Portal.Shared/IoTHub.Portal.Shared.csproj

@@ -29,6 +29,6 @@
     </PackageReference>
     <PackageReference Include="MudBlazor" Version="6.11.0" />
     <PackageReference Include="xunit.extensibility.core" Version="2.6.4" />
-    <PackageReference Include="xunit.extensibility.execution" Version="2.5.3" />
+    <PackageReference Include="xunit.extensibility.execution" Version="2.6.4" />
   </ItemGroup>
 </Project>