Grammatical fix: "set up" is two words (except when it's a noun) (#9516)

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www/src/pages/index.js

@@ -74,7 +74,7 @@ class IndexRoute extends React.Component {
                       {` `}
                       <TechWithIcon icon={WebpackIcon}>Webpack</TechWithIcon>,
                       {` `}
-                      modern JavaScript and CSS and more — all setup and waiting
+                      modern JavaScript and CSS and more — all set up and waiting
                       for you to start building.
                     </FuturaParagraph>
                   </Card>