Update microsite's demos page to link to demo site

Updating the intro paragraph on backstage.io/demos to include a link to demo.backstage.io.

microsite/pages/en/demos.js

@@ -17,22 +17,21 @@ const Background = props => {
       <Block small className="stripe-bottom bg-black-grey">
         <Block.Container style={{ justifyContent: 'flex-start' }}>
           <Block.TextBox>
-            <Block.Title>See us in action.</Block.Title>
+            <Block.Title>See us in action</Block.Title>
             <Block.Paragraph>
-              To illustrate the potential of Backstage, we’re showing you{' '}
-              <a href="https://labs.spotify.com/2020/04/21/how-we-use-backstage-at-spotify/">
-                how we use it here at Spotify
+              To explore the UI and basic features of Backstage firsthand, go to: {' '}
+              <a href="https://demo.backstage.io">
+              demo.backstage.io
               </a>
-              . The videos below feature the custom plugins and templates that
-              we built for our internal version of Backstage. You can use
-              Backstage to build the developer portal you want — integrating the
-              tools that you use in your own infrastructure ecosystem. (Or get
-              started by building an open source plugin for Backstage that
-              everyone can use, like our{' '}
-              <a href="https://backstage.io/blog/2020/04/06/lighthouse-plugin">
-                Lighthouse Plugin
+              . 
+            </Block.Paragraph>
+            <Block.Paragraph>
+              Watch the videos below to get an introduction to Backstage and 
+              to see how we use different plugins to customize {' '}
+              <a href="https://https://labs.spotify.com/2020/04/21/how-we-use-backstage-at-spotify/">
+              our internal version of Backstage at Spotify
               </a>
-              .)
+              .
             </Block.Paragraph>
           </Block.TextBox>
           <Block.Graphics>