Remove edit server mode

It just doesn't really make sense

bookwyrm/templates/settings/federated_server.html

@@ -11,14 +11,6 @@
 <a href="{% url 'settings-federation' %}" class="has-text-weight-normal help">{% trans "Back to server list" %}</a>
 {% endblock %}
 
-{% block edit-button %}
-<a href="{% url 'settings-edit-federated-server' server.id %}">
-    <span class="icon icon-pencil" title="{% trans 'Edit server' %}">
-        <span class="is-sr-only">{% trans "Edit server" %}</span>
-    </span>
-</a>
-{% endblock %}
-
 {% block panel %}
 <div class="columns">
     <section class="column is-half content">