Remove some BUI boilerplate (#28399)

* Remove some BUI boilerplate

- The disposals overrides got removed due to the helper method handling it.
- Replace window creation with CreateWindow helper.
- Fixed some stinky code which would cause exceptions.

* More

* moar

* weh

* done

* More BUIs

* More updates

* weh

* moar

* look who it is

* weh

* merge

* weh

* fixes

Content.Client/Power/APC/ApcBoundUserInterface.cs

@@ -2,6 +2,7 @@
 using Content.Shared.APC;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
+using Robust.Client.UserInterface;
 
 namespace Content.Client.Power.APC
 {
@@ -19,9 +20,8 @@ namespace Content.Client.Power.APC
         {
             base.Open();
 
-            _menu = new ApcMenu(this);
-            _menu.OnClose += Close;
-            _menu.OpenCentered();
+            _menu = this.CreateWindow<ApcMenu>();
+            _menu.OnBreaker += BreakerPressed;
         }
 
         protected override void UpdateState(BoundUserInterfaceState state)
@@ -36,15 +36,5 @@ namespace Content.Client.Power.APC
         {
             SendMessage(new ApcToggleMainBreakerMessage());
         }
-
-        protected override void Dispose(bool disposing)
-        {
-            base.Dispose(disposing);
-
-            if (disposing)
-            {
-                _menu?.Dispose();
-            }
-        }
     }
 }