Correct stripe plugin documentation local use webhook url (#7144)

## Description
The stripe plugin documentation has an error in the forwarding URL for
local development (`/stripe/webhooks` instead of `/api/stripe/webhooks`)

Spent a day debugging my application because the URL in the docs is
wrong. Hoping to save others some time with this correction.

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it fixes. Please also include relevant motivation and context. -->

- [x] I have read and understand the
[CONTRIBUTING.md](https://github.com/payloadcms/payload/blob/main/CONTRIBUTING.md)
document in this repository.

## Type of change

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- [x] Documentation correction

docs/plugins/stripe.mdx

@@ -114,7 +114,7 @@ const res = await fetch(`/api/stripe/rest`, {
 Development:
 
 1. Login using Stripe cli `stripe login`
-1. Forward events to localhost `stripe listen --forward-to localhost:3000/stripe/webhooks`
+1. Forward events to localhost `stripe listen --forward-to localhost:3000/api/stripe/webhooks`
 1. Paste the given secret into your `.env` file as `STRIPE_WEBHOOKS_ENDPOINT_SECRET`
 
 Production: