Fix outbrain not removed after auth'd

The variable name changed. This seems to be the only one left.

Perhaps we need a formal method from Outbrain to remove?

ui/effects/use-ad-outbrain.js

@@ -10,7 +10,7 @@ function inIFrame() {
 }
 
 const LOAD_AD_DELAY_MS = 3000; // Wait past boot-up and core-vitals period.
-const OUTBRAIN_CONTAINER_KEY = 'outbrainStickyParent';
+const OUTBRAIN_CONTAINER_KEY = 'outbrainSizeDiv';
 
 let script;