docs: Fixed old reference to throwing redirects in SvelteKit tutorial (#1150)

Fixed old reference to throwing redirects

This is remaining work from [the tutorial update from SvelteKit 1 to 2](1fc5055#diff-bf2d1cf2d0668155a5de372c1a78a12e766e3a6f51ac7aa552c2771c24564c27).

Author: apike

apps/svelte.dev/content/tutorial/03-sveltekit/09-errors-and-redirects/04-redirects/index.md

@@ -2,7 +2,7 @@
 title: Redirects
 ---
 
-We can also use the `throw` mechanism to redirect from one page to another.
+We can use the `redirect` mechanism to redirect from one page to another.
 
 Create a new `load` function in `src/routes/a/+page.server.js`: