Fix bug in deploy-app recipe
Fix bug in deploy-app recipe

Allow the commands to delete the previous app in the deploy-app recipe
to fail [[1]]. If for some reason the existing app has the wrong name or
isn't present, we still want the deployed app to be renamed to have the
right name.

[1]: https://www.gnu.org/software/make/manual/html_node/Errors.html#Errors

alphagov/digitalmarketplace-aws,alphagov/digitalmarketplace-aws,alphagov/digitalmarketplace-aws