fix(polyfill): dedupe hooks.addEventListener calls (#406)

* fix(polyfill): dont call hooks.addEventListener when rejecting duplicate listeners in EventTarget.addEventListener

* Add changeset

---------

Co-authored-by: Chris Sauve <chris.sauve@shopify.com>

.changeset/loud-steaks-argue.md

@@ -0,0 +1,5 @@
+---
+'@remote-dom/polyfill': patch
+---
+
+Fixes `hooks.addEventListener()` being called even when `EventTarget.addEventListener()` rejects a duplicate listener registration

packages/polyfill/source/EventTarget.ts

@@ -56,7 +56,7 @@ export class EventTarget {
       listeners.set(key, list);
     }
 
-    list.add(normalizedListener);
+    if (list.has(normalizedListener)) return;
 
     signal?.addEventListener(
       'abort',
@@ -66,6 +66,7 @@ export class EventTarget {
       {once: true},
     );
 
+    list.add(normalizedListener);
     hooks.addEventListener?.(this as any, type, listener, options);
   }