Bump xunit from 2.4.2 to 2.5.0 (#286)

Bumps [xunit](https://github.com/xunit/xunit) from 2.4.2 to 2.5.0.
- [Commits](xunit/xunit@2.4.2...2.5.0)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Steve Smith <steve@kentsmiths.com>

Author: dependabot[bot]

test/GuardClauses.UnitTests/GuardClauses.UnitTests.csproj

@@ -18,7 +18,7 @@
         </PackageReference>
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.6.2" />
         <PackageReference Include="ReportGenerator" Version="5.1.22" />
-        <PackageReference Include="xunit" Version="2.4.2" />
+        <PackageReference Include="xunit" Version="2.5.0" />
         <PackageReference Include="xunit.runner.visualstudio" Version="2.4.5" />
     </ItemGroup>