specify honcho instead of run_dammit

#468 (comment)

www/howto/run-payday.spt

@@ -9,7 +9,7 @@ ticket created in step two.
   1. [Start a ticket](https://github.com/gratipay/inside.gratipay.com/issues/new) named "run Gratipay NNN."
   1. Locate and, in the ticket description, link to the ticket for the previous payday. Linked list!
   1. [Review accounts](./review-accounts).
-  1. Migrate tips: `heroku config -s | run_dammit /dev/stdin -c ./env/bin/python ./bin/migrate-tips.py > migrate-tips.log`
+  1. Migrate tips: `heroku config -s -a gratipay | ./env/bin/honcho run -e /dev/stdin ./env/bin/python ./bin/migrate-tips.py > migrate-tips.log`
   1. Take a backup using `bin/snapper.py`. Load the backup locally and make sure the `/explore/` page
      matches the production `/explore/` page.
   1. Triple-check the [stats page](https://gratipay.com/about/stats) to get the week