UnrealGameSync update check not working if Horde is set as an update source

This was reported by a customer using Horde as an update source.

It seems like we discovered a bug in UGS that causes update checks not to work. The regular updates while UGS is running, not the initial check when it is being launched

• The build of the UGS must be the one that has auto updates enabled (standard BuildGraph installation build for example, not debug build.)
• The retrieval of the service from _serviceProvider fails.

In /Engine/Source/Programs/UnrealGameSync/UnrealGameSync/UpdateMonitor.cs

public async Task CheckForUpdatesLoopAsync(CancellationToken cancellationToken)
{
...
    // ERROR HERE: Incorrectly tries to get HordeHttpClient as a service.
    HordeHttpClient hordeHttpClient = _serviceProvider.GetRequiredService<HordeHttpClient>();
 
    // SOLUTION: We need to ask for IHordeClient and create a client from that.
    using HordeHttpClient hordeHttpClient = _serviceProvider.GetRequiredService<IHordeClient>().CreateHttpClient();
...
}