docs: typo in migration.md (#8895)

Author: sepehr-safari

docs/guide/migration.md

@@ -27,7 +27,7 @@ A small fraction of users will now require using [@vitejs/plugin-legacy](https:/
   - `build.polyfillDynamicImport` (use [`@vitejs/plugin-legacy`](https://github.com/vitejs/vite/tree/main/packages/plugin-legacy) for browsers without dynamic import support)
   - `optimizeDeps.keepNames` (switch to [`optimizeDeps.esbuildOptions.keepNames`](../config/dep-optimization-options.md#optimizedeps-esbuildoptions))
 
-## Achitecture changes and legacy Options
+## Architecture changes and legacy Options
 
 This section describes the biggest architecture changes in Vite v3. To allow projects to migrate from v2 in case of a compat issue, legacy options have been added to revert to the Vite v2 strategies.