Update usages of ! is with is not (#2584)

* Update usages of ! is with is not

* Content.IntegrationTests commit

* Content.Server commit

* Content.Shared commit

Co-authored-by: Metal Gear Sloth <metalgearsloth@gmail.com>

Content.Server/GameObjects/Components/Medical/MedicalScannerComponent.cs

@@ -258,7 +258,7 @@ namespace Content.Server.GameObjects.Components.Medical
 
         private void OnUiReceiveMessage(ServerBoundUserInterfaceMessage obj)
         {
-            if (!(obj.Message is UiButtonPressedMessage message)) return;
+            if (obj.Message is not UiButtonPressedMessage message) return;
 
             switch (message.Button)
             {