Update invitation styling

src/backoffice/templates/backoffice/assemblies/components/invitations.html

@@ -3,8 +3,8 @@
 {% if received_invitations %}
   <div class="row mt-3">
     <div class="col-md-12">
-      <div class="card">
-        <div class="card-header">{% trans "Assembly__invitation_pending__title" %}</div>
+      <div class="card border-primary">
+        <div class="card-header text-bg-primary">{% trans "Assembly__invitation_pending__title" %}</div>
         <ul class="list-group">
           {% for invitation in received_invitations %}
             <li class="list-group-item">