Upgrade to fontawesome 6

* Adapt fontawesome usage when needed
* Fix uv guide not importing css
* Remove utf8 usage for fontawesome

pedagogy/templates/pedagogy/uv_detail.jinja

@@ -2,6 +2,10 @@
 {% from "core/macros.jinja" import user_profile_link %}
 {% from "pedagogy/macros.jinja" import display_star %}
 
+{% block additional_css %}
+  <link rel="stylesheet" href="{{ static('pedagogy/css/pedagogy.scss') }}">
+{% endblock %}
+
 {% block title %}
   {% trans %}UV Details{% endtrans %}
 {% endblock %}