fix(billing): Update docs to reflect new UI

docs/pricing/legacy-pricing.mdx

@@ -178,7 +178,7 @@ If the amount of prepaid data you want to buy falls in between increments, you m
 
 Use the slider on the [pricing](https://sentry.io/pricing/) page to determine the amount of prepaid data you might need based on the volume of event types you send.
 
-![Reserved Volume settings in Subscriptions](./img/reserved-volume.png)
+![Reserved Volume settings in checkout](./img/reserved-volume.png)
 
 For more information on how to manage your monthly spending, check out our [Quota Management documentation](/pricing/quotas/).
 
@@ -214,7 +214,7 @@ Organizations on all plans have the option to set a shared on-demand strategy. O
 
 - **Per-category:** Your on-demand budgets for categories such as errors, transactions, and replays, are set up individually so that any overages in one category won't consume the budget of another category.
 
-![On-Demand Budgets settings in Subscriptions](./img/on-demand-budgets.png)
+![On-Demand Budgets settings in Subscription](./img/on-demand-budgets.png)
 
 <Alert>
   Seer and logs are only available through a shared on-demand budget.

docs/pricing/quotas/index.mdx

@@ -11,7 +11,7 @@ To see which projects are using up your quota, you can review the "Usage" tab of
 
 ![Overview of Usage Stats page](./img/usage-stats-errors.png)
 
-You can also download a project breakdown report in the "Usage History" tab of **Settings > Subscriptions** (only accessible to Owner and Billing members of your Sentry organization).
+You can also download a project breakdown report by clicking the "View all usage" button in **Settings > Subscription** (only accessible to Owner and Billing members of your Sentry organization).
 
 Sentry's flexibility means you can exercise fine-grained control over which events and attachments count toward your quota. This page provides you with high-level information about strategies for managing your quota, but you can get more detailed information in:
 

docs/pricing/quotas/legacy-manage-transaction-quota.mdx

@@ -107,9 +107,9 @@ If you have an annual billing period, plan downgrades and decreases in reserved
 
 Changes to on-demand volume typically go into effect immediately and are guaranteed to go into effect within 24 hours. However, you can't decrease your on-demand budget to less than what you've consumed in the current period.
 
-To decrease your quota, go to **Settings > Subscription** and click "Manage Subscriptions". When you reach the "Review & Confirm" step, the date that these changes go into effect will be displayed:
+To decrease your quota, go to **Settings > Subscription** and click "Manage plan". The cart will display the date that these changes will go into effect:
 
-![The Review & Confirm step of a subscription update.](./img/review-subscription.png)
+![The cart of a subscription update.](./img/cart.png)
 
 <Alert>
 

docs/product/alerts/notifications/index.mdx

@@ -61,9 +61,9 @@ Learn more in the [Pricing & Billing docs](/pricing/quotas/).
 
 ### Spend Notifications for Your Organization
 
-Billing or owner members can set up their notification thresholds by going to: **Settings > Subscriptions > Notifications**.
+Billing or owner members can set up their notification thresholds by going to: **Settings > Subscription > Manage Spend Notifications**.
 
-![Notifications tab of Subscription settings page](./img/subscription_notifications_settings.png)
+![Manage Spend Notifications page](./img/subscription_notifications_settings.png)
 
 From here, you can customize the notification thresholds for your organization for when you're close to reaching one or both of the below: