wrap carousel in section tag for improved structure

includes/index-hero.php

@@ -1,3 +1,4 @@
+<section>
 <div id="carouselExampleIndicators" class="carousel slide js-fullheight" data-ride="carousel">
     <ol class="carousel-indicators">
         <li data-target="#carouselExampleIndicators" data-slide-to="0" class="active"></li>
@@ -49,4 +50,5 @@
         <span class="carousel-control-next-icon" aria-hidden="true"></span>
         <span class="sr-only">Next</span>
     </a>
-</div>
+</div>
+</section>