move single and all datasets buttons

index.html

@@ -61,8 +61,8 @@
 
       <section class="panel is-active matrix-view" id="leaderboards" role="tabpanel">
         <div class="view-switch" role="group" aria-label="Leaderboard view">
-          <button class="view-button" type="button" data-view="single" aria-pressed="false">Single dataset</button>
           <button class="view-button is-active" type="button" data-view="matrix" aria-pressed="true">All datasets</button>
+          <button class="view-button" type="button" data-view="single" aria-pressed="false">Single dataset</button>
         </div>
 
         <div class="filter-card">