update error log for plugin download

Emby.Server.Implementations/Updates/InstallationManager.cs

@@ -350,7 +350,7 @@ namespace Emby.Server.Implementations.Updates
             var extension = Path.GetExtension(package.SourceUrl);
             if (!string.Equals(extension, ".zip", StringComparison.OrdinalIgnoreCase))
             {
-                _logger.LogError("Only zip packages are supported. {Filename} is not a zip archive.", package.SourceUrl);
+                _logger.LogError("Only zip packages are supported. {SourceUrl} is not a zip archive.", package.SourceUrl);
                 return;
             }