Fix itm_campaign for "buy now" links has wrong value on interstitial payment page (#8632)

GitOrigin-RevId: 58ca6d4453f3cdfcb4f2dea8ddb3f6bc1b73a4fe

services/web/app/src/Features/Subscription/SubscriptionController.js

@@ -98,6 +98,7 @@ async function plansPage(req, res) {
     title: 'plans_and_pricing',
     plans,
     itm_content: req.query && req.query.itm_content,
+    itm_campaign: 'plans',
     recommendedCurrency,
     planFeatures,
     plansV2Config,
@@ -253,6 +254,7 @@ async function interstitialPaymentPage(req, res) {
     res.render('subscriptions/interstitial-payment', {
       title: 'subscribe',
       itm_content: req.query && req.query.itm_content,
+      itm_campaign: req.query?.itm_campaign,
       recommendedCurrency,
       interstitialPaymentConfig,
     })

services/web/app/views/subscriptions/plans-marketing/v2/_mixins.pug

@@ -455,10 +455,11 @@ mixin additional_link_group(eventTrackingKey, additionalEventSegmentation, plan)
 mixin additional_link_buy(eventTrackingKey, additionalEventSegmentation, plan, period)
 	- var buttonSegmentation = plan + '-link'
 	- var segmentation = JSON.stringify(Object.assign({}, {button: buttonSegmentation, location: 'table-header', period}, additionalEventSegmentation))
+	- var qs = new URLSearchParams({planCode: plan, currency: recommendedCurrency, itm_campaign, itm_content: 'card'})
 	small.plans-v2-table-th-content-additional-link
 		| #{translate("or")} 
 		a(
-			href="/user/subscription/new?planCode=" + plan + "&currency=" + recommendedCurrency + "&itm_campaign=plans&itm_content=card"
+			href=`/user/subscription/new?${qs.toString()}`
 			event-tracking=eventTrackingKey
 			event-tracking-mb="true"
 			event-tracking-trigger="click"