Backport pull request #11633 from jellyfin/release-10.9.z

Allow empty user id when getting device list

Original-merge: a5d60c4521dd94b084fd8eb7ca99f93d4eda99fa

Merged-by: crobibero <cody@robibe.ro>

Backported-by: Joshua M. Boniface <joshua@boniface.me>

Jellyfin.Server.Implementations/Devices/DeviceManager.cs

@@ -179,7 +179,7 @@ namespace Jellyfin.Server.Implementations.Devices
                     .SelectMany(d => dbContext.DeviceOptions.Where(o => o.DeviceId == d.DeviceId).DefaultIfEmpty(), (d, o) => new { Device = d, Options = o })
                     .AsAsyncEnumerable();
 
-                if (userId.HasValue)
+                if (!userId.IsNullOrEmpty())
                 {
                     var user = _userManager.GetUserById(userId.Value);
                     if (user is null)