Bump xunit.runner.visualstudio from 3.1.4 to 3.1.5 (#679)

---
updated-dependencies:
- dependency-name: xunit.runner.visualstudio
  dependency-version: 3.1.5
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

tests/Giraffe.Tests/Giraffe.Tests.fsproj

@@ -46,7 +46,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.*" />
     <PackageReference Include="xunit" Version="2.9.*" />
-    <PackageReference Include="xunit.runner.visualstudio" Version="3.1.4">
+    <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>