Bump Xunit.SkippableFact from 1.4.13 to 1.5.23

Bumps [Xunit.SkippableFact](https://github.com/AArnott/Xunit.SkippableFact) from 1.4.13 to 1.5.23.
- [Release notes](https://github.com/AArnott/Xunit.SkippableFact/releases)
- [Commits](AArnott/Xunit.SkippableFact@v1.4.13...v1.5.23)

---
updated-dependencies:
- dependency-name: Xunit.SkippableFact
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

tests/BlurHashSharp.Tests/BlurHashSharp.Tests.csproj

@@ -11,7 +11,7 @@
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
     <PackageReference Include="xunit" Version="2.9.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" />
-    <PackageReference Include="Xunit.SkippableFact" Version="1.4.13" />
+    <PackageReference Include="Xunit.SkippableFact" Version="1.5.23" />
     <PackageReference Include="coverlet.collector" Version="6.0.2" />
   </ItemGroup>