Format report text with kramdown

Pass the text of reports ('details' field) through the RichText formatter to give us kramdown formatting support.

app/models/report.rb

@@ -36,4 +36,8 @@ class Report < ApplicationRecord
     else %w[other]
     end
   end
+
+  def details
+    RichText.new("markdown", self[:details])
+  end
 end

app/views/issues/_reports.html.erb

@@ -9,7 +9,7 @@
                                    :user => link_to(report.user.display_name, user_path(report.user)),
                                    :updated_at => l(report.updated_at.to_datetime, :format => :friendly) %>
       </p>
-      <p><%= report.details %></p>
+      <p class="richtext text-break"><%= report.details.to_html %></p>
     </div>
   </div>
   <hr>