Bump Microsoft.Extensions.Logging from 3.1.5 to 3.1.6

Bumps [Microsoft.Extensions.Logging](https://github.com/aspnet/Extensions) from 3.1.5 to 3.1.6.
- [Release notes](https://github.com/aspnet/Extensions/releases)
- [Commits](dotnet/extensions@v3.1.5...v3.1.6)

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

NuGetKeyVaultSignTool.Core/NuGetKeyVaultSignTool.Core.csproj

@@ -6,7 +6,7 @@
 
   <ItemGroup>
     <PackageReference Include="Azure.Security.KeyVault.Certificates" Version="4.0.3" />
-    <PackageReference Include="Microsoft.Extensions.Logging" Version="3.1.5" />
+    <PackageReference Include="Microsoft.Extensions.Logging" Version="3.1.6" />
     <PackageReference Include="NuGet.Packaging" Version="5.6.0-xprivate.60020" />
     <PackageReference Include="NuGet.Protocol" Version="5.6.0-xprivate.60020" />    
     <PackageReference Include="RSAKeyVaultProvider" Version="2.1.1" />