views: factor out FontAwesome icons.

Factor out FontAwesome icons into a set of helpers. This is so that it's
easier to keep track of which icons we're using and easier to change
icons globally.

app/components/comment_component/comment_component.html.erb

@@ -89,21 +89,18 @@
           <% if policy(comment).update? %>
             <%= menu.item do %>
               <%= link_to edit_comment_path(comment.id), id: "edit_comment_link_#{comment.id}", class: "edit_comment_link" do %>
-                <i class="icon fas fa-edit"></i>
-                Edit
+                <%= edit_icon %> Edit
               <% end %>
             <% end %>
 
             <%= menu.item do %>
               <% if comment.is_deleted? %>
                 <%= link_to undelete_comment_path(comment.id), method: :post, remote: true do %>
-                  <i class="icon fas fa-trash-restore-alt"></i>
-                  Undelete
+                  <%= undelete_icon %> Undelete
                 <% end %>
               <% else %>
                 <%= link_to comment_path(comment.id), "data-confirm": "Are you sure you want to delete this comment?", method: :delete, remote: true do %>
-                  <i class="icon fas fa-trash-alt"></i>
-                  Delete
+                  <%= delete_icon %> Delete
                 <% end %>
               <% end %>
             <% end %>
@@ -112,8 +109,7 @@
           <% if policy(comment).reportable? %>
             <%= menu.item do %>
               <%= link_to new_moderation_report_path(moderation_report: { model_type: "Comment", model_id: comment.id }), remote: true do %>
-                <i class="icon fas fa-flag"></i>
-                Report
+                <%= flag_icon %> Report
               <% end %>
             <% end %>
           <% end %>