Replace fontawesome with latest version 6.5.2 (#116)

templates/problem/feed/items.html

@@ -15,7 +15,7 @@
     {% with authors=problem.get_authors() %}
       {% if authors %}
         <div class="problem-feed-info-entry">
-          <i class="fa fa-pencil-square-o fa-fw"></i>
+          <i class="far fa-pen-to-square"></i>
           <span class="pi-value">{{ link_users(authors) }}</span>
         </div>
       {% endif %}

templates/problem/left-sidebar.html

@@ -1,6 +1,6 @@
 {% if not show_contest_mode %}
   <div class="left-sidebar">
-    {{ make_tab_item('feed', 'fa fa-pagelines', url('problem_feed'), _('Feed')) }}
+    {{ make_tab_item('feed', 'far fa-lightbulb', url('problem_feed'), _('Feed')) }}
     {{ make_tab_item('list', 'fa fa-list', url('problem_list'), _('List')) }}
     {% if request.user.is_superuser %}
       {{ make_tab_item('admin', 'fa fa-edit', url('admin:judge_problem_changelist'), _('Admin'), force_new_page=True) }}

templates/problem/problem.html

@@ -259,7 +259,7 @@
 {% with authors=problem.get_authors() %}
   {% if authors %}
     <div class="problem-info-entry">
-      <i class="fa fa-pencil-square-o fa-fw"></i><span
+      <i class="far fa-pen-to-square"></i><span
         class="pi-name">{% trans trimmed count=authors|length %}
           Author:
           {% pluralize count %}