Update dotnet msbuild to 17.12.6

Author: renovate[bot]

Directory.Packages.support.props

@@ -2,9 +2,9 @@
 
 <Project>
     <ItemGroup Condition="'$(TargetFramework)' == 'net8.0'">
-        <PackageVersion Update="Microsoft.Build" Version="17.11.4" />
-        <PackageVersion Update="Microsoft.Build.Framework" Version="17.11.4" />
-        <PackageVersion Update="Microsoft.Build.Tasks.Core" Version="17.11.4" />
-        <PackageVersion Update="Microsoft.Build.Utilities.Core" Version="17.11.4" />
+        <PackageVersion Update="Microsoft.Build" Version="17.12.6" />
+        <PackageVersion Update="Microsoft.Build.Framework" Version="17.12.6" />
+        <PackageVersion Update="Microsoft.Build.Tasks.Core" Version="17.12.6" />
+        <PackageVersion Update="Microsoft.Build.Utilities.Core" Version="17.12.6" />
     </ItemGroup>
 </Project>