Code cleanup (#660)

* Remove trailing whitespace

* Clean up donate page

* Format index and remove unnecessary breaklines

* Fix p element being child of ul error

* Fix empty h1 error

* Losslessly compress mailbox, mastodon and bitwarden images

_includes/card.html

@@ -22,7 +22,7 @@
             <p><img src="{{include.image}}" alt="{{include.title}}" class="panel-item">{{include.description}}</p>
             <div>
             <p>
-                <a class="btn btn-{{include.color}} mb-1" href="{{include.url}}">Website: 
+                <a class="btn btn-{{include.color}} mb-1" href="{{include.url}}">Website:
                     {% if include.website %}
                         {{include.website}}
                     {% else %}