Fix HTML closing tags

In some places, we accidentally opened the same tag twice instead of
closing it, while in some other places we closed a tag without opening
it in the first place.

We've detected these issues thanks to the HTML Beautifier gem, which
we're about to start using for indentation purposes.

app/components/budgets/ballot/ballot_component.html.erb

@@ -9,7 +9,7 @@
     </h2>
     <p class="confirmed">
       <%= t("budgets.ballots.show.voted_info") %>
-    <p>
+    </p>
     <p><%= t("budgets.ballots.show.voted_info_2") %></p>
   </div>
 </header>