Creates a new event subscription. You have the option to create a
temporary subscription using server-sent events or a persistent
subscription using webhooks.

If you choose a temporary subscription, it will be automatically
deleted if it no clients are subscribed to it for the duration
specified in timeToLiveSeconds.

If you opt for a persistent subscription, it will remain active as
long as you respond to the webhook messages sent to your provided URL
with a 200 OK status. If we are unable to deliver events to your webhook
continuously for 90 days, the subscription will be disabled.