[release/9.0.1xx] [StaticWebAssets] Fix legacy package definitions design time builds (#43937)

Co-authored-by: Javier Calvarro Nelson <[email protected]>

Author: github-actions[bot]

src/StaticWebAssetsSdk/Targets/Microsoft.NET.Sdk.StaticWebAssets.targets

@@ -694,7 +694,7 @@ Copyright (c) .NET Foundation. All rights reserved.
 
   </Target>
 
-  <Target Name="UpdateExistingPackageStaticWebAssets" Condition="'$(DesignTimeBuild)' != 'true'">
+  <Target Name="UpdateExistingPackageStaticWebAssets">
     <UpdatePackageStaticWebAssets Assets="@(StaticWebAsset)">
       <Output TaskParameter="UpdatedAssets" ItemName="_UpdatedPackageAssets" />
       <Output TaskParameter="OriginalAssets" ItemName="_OriginalPackageAssets" />