change a word subsequent

README.md

@@ -47,7 +47,7 @@ pages:
 ```
 
 This sets up a `node9.11.1` environment, then uses `yarn install` to install dependencies and `yarn build` to build out the website to the `./public` directory.
-It also caches the `node_modules` directory to speed up sebsequent builds.
+It also caches the `node_modules` directory to speed up subsequent builds.
 
 ## Building locally