Fix some warnings relating to fields being unused.

Content.Server/GameTicking/GameTicker.cs

@@ -84,7 +84,6 @@ namespace Content.Server.GameTicking
         [Dependency] private readonly IServerPreferencesManager _prefsManager = default!;
         [Dependency] private readonly IBaseServer _baseServer = default!;
         [Dependency] private readonly IWatchdogApi _watchdogApi = default!;
-        [Dependency] private readonly IEntitySystemManager _entitySystemManager = default!;
         [Dependency] private readonly IReflectionManager _reflectionManager = default!;
     }
 }