Tidy up conditional message

lib/gitlab/slash_commands/presenters/help.rb

@@ -43,13 +43,15 @@ module Gitlab
         end
 
         def help_footer
-          <<~MESSAGE
-            #{project_info if @project}
+          message = @project ? project_info : ''
+          message += <<~MESSAGE
              *Documentation*
 
              For more information about GitLab chatops, refer to its
              documentation: https://docs.gitlab.com/ce/ci/chatops/README.html.
           MESSAGE
+
+          message
         end
 
         def project_info