Update dotnet monorepo to v9

Author: renovate[bot]

SIL.NuGetCleaner/SIL.NuGetCleaner.csproj

@@ -30,11 +30,11 @@ See full changelog at https://github.com/sillsdev/SIL.NuGetCleaner/blob/master/C
     <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
     <PackageReference Include="NuGet.Versioning" Version="6.14.0" />
     <PackageReference Include="SIL.ReleaseTasks" Version="3.1.1" PrivateAssets="all" />
-    <PackageReference Include="System.Drawing.Common" Version="8.0.18" />
+    <PackageReference Include="System.Drawing.Common" Version="9.0.8" />
     <PackageReference Include="System.Globalization.Extensions" Version="4.3.0" />
     <PackageReference Include="System.Net.Http" Version="4.3.4" />
     <PackageReference Include="System.Security.Principal.Windows" Version="5.0.0" />
-    <PackageReference Include="System.Text.Encoding.CodePages" Version="8.0.0" />
+    <PackageReference Include="System.Text.Encoding.CodePages" Version="9.0.8" />
   </ItemGroup>
 
 </Project>