fix(editor): Fix Webhook URL expansion icon (#8011)

Changes the rotation of the icon. 

New collapsed:
![Screenshot from 2023-12-13
12-06-12](https://github.com/n8n-io/n8n/assets/6249596/2991a660-d6b4-4272-88cf-6a2356d02a7e)

New expanded:
![Screenshot from 2023-12-13
12-06-22](https://github.com/n8n-io/n8n/assets/6249596/0766db9e-b868-49a8-9009-dfff4ab0b13b)

packages/editor-ui/src/components/NodeWebhooks.vue

@@ -6,7 +6,7 @@
 			@click="isMinimized = !isMinimized"
 			:title="isMinimized ? baseText.clickToDisplay : baseText.clickToHide"
 		>
-			<font-awesome-icon icon="angle-down" class="minimize-button minimize-icon" />
+			<font-awesome-icon icon="angle-right" class="minimize-button minimize-icon" />
 			{{ baseText.toggleTitle }}
 		</div>
 		<el-collapse-transition>
@@ -231,10 +231,10 @@ export default defineComponent({
 	transition-property: transform;
 }
 .expanded .minimize-button {
-	-webkit-transform: rotate(180deg);
-	-moz-transform: rotate(180deg);
-	-o-transform: rotate(180deg);
-	transform: rotate(180deg);
+	-webkit-transform: rotate(90deg);
+	-moz-transform: rotate(90deg);
+	-o-transform: rotate(90deg);
+	transform: rotate(90deg);
 }
 
 .webhook-url {