* We need to add a Free Trials section to the Sub Manage page so that a customer can see what free trials they have.
This commit:
* Adds a new Free Trial section and component, to be rendered on the Subscription Management page, akin to “Payment details” and “Active subscriptions”, that is only rendered if a user has an active trialing subscription.
* If the free trial is active, includes details about their upcoming billing cycle, and the option to cancel their free trial
* If the free trial could not be converted due to a failed payment method, includes invoice details, and the option to update their payment info
* Implements UI for both Desktop and Mobile views
Closes #[PAY-3547](https://mozilla-hub.atlassian.net/browse/PAY-3547)