Bump Microsoft.AspNetCore.TestHost in /FeatureFlags/FeatureFlags.Tests

Bumps [Microsoft.AspNetCore.TestHost](https://github.com/dotnet/aspnetcore) from 5.0.5 to 5.0.6.
- [Release notes](https://github.com/dotnet/aspnetcore/releases)
- [Commits](dotnet/aspnetcore@v5.0.5...v5.0.6)

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

FeatureFlags/FeatureFlags.Tests/FeatureFlags.Tests.csproj

@@ -27,7 +27,7 @@
     <PackageReference Include="Microsoft.AspNetCore.HttpsPolicy" Version="2.2.0" />
     <PackageReference Include="Microsoft.AspNetCore.Mvc" Version="2.2.0" />
     <PackageReference Include="Microsoft.AspNetCore.Mvc.Core" Version="2.2.5" />
-    <PackageReference Include="Microsoft.AspNetCore.TestHost" Version="5.0.5" />
+    <PackageReference Include="Microsoft.AspNetCore.TestHost" Version="5.0.6" />
     <PackageReference Include="Microsoft.Extensions.Configuration" Version="5.0.0" />
     <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="5.0.0" />
     <PackageReference Include="Microsoft.Extensions.Configuration.UserSecrets" Version="5.0.0" />