Adds API token information. (#18014)

Author: angelampcosta

src/content/docs/spectrum/about/byoip.mdx

@@ -75,4 +75,4 @@ curl "https://api.cloudflare.com/client/v4/zones/{zone_id}/spectrum/apps" \
 }'
 ```
 
-Replace `{zone_id}`, `<EMAIL>`, and `<API_KEY>` with your actual values.
+Replace `{zone_id}`, `<EMAIL>`, and `<API_TOKEN>` with your actual values. Your API token needs to have `IP Prefixes: Write` permissions.