docs: remove suggestion to use npm call out (#525)

Author: stainless-app[bot]

README.md

@@ -321,7 +321,7 @@ The following runtimes are supported:
 
 - Web browsers (Up-to-date Chrome, Firefox, Safari, Edge, and more)
 - Node.js 18 LTS or later ([non-EOL](https://endoflife.date/nodejs)) versions.
-- Deno v1.28.0 or higher, using `import Mux from "npm:@mux/mux-node"`.
+- Deno v1.28.0 or higher.
 - Bun 1.0 or later.
 - Cloudflare Workers.
 - Vercel Edge Runtime.