[Bug]: NuGet SDK client cannot search for packages for a given packageType

[vlada-shubina]

NuGet Product Used

dotnet.exe

Product Version

5.10.0, 6.0.0-preview.2.129

Worked before?

No response

Impact

It's more difficult to complete my work

Repro Steps & Context

Product is NuGet Client SDK.
Requirement: search for all packages of package type Template using NuGet SDK:

Code:

            SourceRepository repository = Repository.Factory.GetCoreV3("https://api.nuget.org/v3/index.json");
            var searchResource = await repository.GetResourceAsync<PackageSearchResource>().ConfigureAwait(false);

            var searchFilter = new SearchFilter(includePrerelease: true);
            searchFilter.PackageTypes = new[] { "Template" };
            var searchResult = await searchResource.SearchAsync("", searchFilter, 0, 10, NullLogger.Instance, default);

            foreach (var pack in searchResult)
            {
                Console.WriteLine(pack.Identity.Id);
            }    

Output:

Newtonsoft.Json
Microsoft.Extensions.DependencyInjection
Microsoft.Extensions.Logging
Serilog
Microsoft.EntityFrameworkCore
Castle.Core
Moq
Microsoft.Bcl.AsyncInterfaces
AutoMapper
Microsoft.ApplicationInsights

Expected: only packages of template type is returned.
Actual: packages of any type is returned

Related: dotnet/templating#3498

Note: using https://azuresearch-ussc.nuget.org/query?packageType=Template&skip=0&take=10&prerelease=true works as expected.

Verbose Logs

not applicable

[zivkan]

Duplicate of #8915. Please add a 👍 reaction there.