Cleanup warnings in PolymorphSystem.Map (#36869)

Fix warnings in PolymorphSystem.Map

Content.Server/Polymorph/Systems/PolymorphSystem.Map.cs

@@ -31,8 +31,7 @@ public sealed partial class PolymorphSystem
         if (PausedMap != null && Exists(PausedMap))
             return;
 
-        var newmap = _mapManager.CreateMap();
-        _mapManager.SetMapPaused(newmap, true);
-        PausedMap = _mapManager.GetMapEntityId(newmap);
+        PausedMap = _map.CreateMap();
+        _map.SetPaused(PausedMap.Value, true);
     }
 }

Content.Server/Polymorph/Systems/PolymorphSystem.cs

@@ -29,7 +29,7 @@ namespace Content.Server.Polymorph.Systems;
 public sealed partial class PolymorphSystem : EntitySystem
 {
     [Dependency] private readonly IComponentFactory _compFact = default!;
-    [Dependency] private readonly IMapManager _mapManager = default!;
+    [Dependency] private readonly SharedMapSystem _map = default!;
     [Dependency] private readonly IPrototypeManager _proto = default!;
     [Dependency] private readonly IGameTiming _gameTiming = default!;
     [Dependency] private readonly ActionsSystem _actions = default!;