Don't allow other mods to consume builder early

Author: Rune580

LethalCompanyInputUtils/Api/InputActionMapBuilder.cs

@@ -23,7 +23,7 @@ public InputActionBindingBuilder NewActionBinding()
         return new InputActionBindingBuilder(this);
     }
 
-    public InputActionMap Build()
+    internal InputActionMap Build()
     {
         return _actionMap;
     }