Tiny Typo fix (#9371)

docs/guides/single-fetch.md

@@ -17,7 +17,7 @@ When you enable Single Fetch, Remix will make a single HTTP call to your server
 - You must add `node_modules/@remix-run/react/future/single-fetch.d.ts` to the end of your `tsconfig.json`'s `include` array to get proper type inference
 - Revalidation after an `action` `4xx`/`5xx` `Response` is now opt-in, versus opt-out
 - The [`headers`][headers] function is no longer used when Single Fetch is enabled, in favor of the new `response` stub passed to your `loader`/`action` functions
-- The old `installGlobals()` polyfill doens't work for Single Fetch, you must either use the native Node 20 `fetch` API or call `installGlobals({ nativeFetch: true })` in your custom server to get the [undici-based polyfill][undici-polyfill]
+- The old `installGlobals()` polyfill doesn't work for Single Fetch, you must either use the native Node 20 `fetch` API or call `installGlobals({ nativeFetch: true })` in your custom server to get the [undici-based polyfill][undici-polyfill]
 
 ## Details