update vercel kv templates (#960)

### Description

Replace `@vercel/kv` by `@upstash/redis` in the following templates:

- `storage/kv-redis-starter`
- `edge-functions/api-rate-limit`
- `storage/kv-redis-nuxt`
- `storage/kv-redis-sveltekit`
- `storage/kv-redis-waiting-room`



### Demo URL

<!--
Provide a URL to a live deployment where we can test your PR. If a demo
isn't possible feel free to omit this section.
-->

### Type of Change

- [ ] New Example
- [ ] Example updates (Bug fixes, new features, etc.)
- [ ] Other (changes to the codebase, but not to examples)

### New Example Checklist

- [ ] 🛫 `npm run new-example` was used to create the example
- [ ] 📚 The template wasn't used but I carefuly read the [Adding a new
example](https://github.com/vercel/examples#adding-a-new-example) steps
and implemented them in the example
- [ ] 📱 Is it responsive? Are mobile and tablets considered?

edge-functions/api-rate-limit/package.json

@@ -12,7 +12,7 @@
   "dependencies": {
     "@upstash/ratelimit": "^0.4.3",
     "@vercel/examples-ui": "^1.0.5",
-    "@vercel/kv": "^0.2.2",
+    "@upstash/redis": "^1.34.3",
     "next": "canary",
     "react": "latest",
     "react-dom": "latest"

edge-functions/api-rate-limit/pages/api/ping.ts

@@ -1,9 +1,13 @@
 import type { NextRequest } from 'next/server'
 import { Ratelimit } from '@upstash/ratelimit'
-import { kv } from '@vercel/kv'
+import { Redis } from '@upstash/redis'
 
+const redis = new Redis({
+  url: process.env.KV_REST_API_URL,
+  token: process.env.KV_REST_API_TOKEN,
+})
 const ratelimit = new Ratelimit({
-  redis: kv,
+  redis,
   // 5 requests from the same IP in 10 seconds
   limiter: Ratelimit.slidingWindow(5, '10 s'),
 })