chore: added meta description

Author: mfranzke

index.html

@@ -4,6 +4,7 @@
     <meta charset="UTF-8" />
     <meta http-equiv="X-UA-Compatible" content="IE=edge" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <meta name="description" content="Overview regarding the technical components out of the DB UX Design System by Deutsche Bahn.">
     <title>DB UI</title>
     <link
       rel="stylesheet"