ci: separate summary elements with <br> element

This makes them look more like buttons.

Author: calcmogul

ci/index.html

@@ -186,7 +186,7 @@ <h3 id="Robot_software">Robot software</h3><a href=
       control of electromechanical systems in FRC. Robot software design
       patterns are covered as well as features of WPILib and FRC team 3512's
       custom classes.</p>
-    </details>
+    </details><br>
     <details>
       <summary class="curriculum">
         Miscellaneous computer science