Add readonly where it is missing and fix those field names according to their modifiers (#2589)

Content.Server/GameObjects/Components/Morgue/BodyBagEntityStorageComponent.cs

@@ -32,7 +32,7 @@ namespace Content.Server.GameObjects.Components.Morgue
         public override string Name => "BodyBagEntityStorage";
 
         [ViewVariables]
-        [ComponentDependency] private AppearanceComponent? _appearance = null;
+        [ComponentDependency] private readonly AppearanceComponent? _appearance = null;
 
         [ViewVariables] public ContainerSlot? LabelContainer { get; private set; }