created bugs have truncated bug tags

[Brian Murray]

When the error tracker creates a bug it is supposed to tag it with the release codename, e.g. wily. If the lookup for the codename fails the release version, 15.10, is used. However, I noticed we were getting bugs tagged 15.1, although pitti's were tagged 16.04. This leads us to believe something is striping the trailing zero.

Places to look include errors/api/resources.py and the release variable, along with daisy/launchpad.py and the release_codenames.

Having said that it looks like errors/api/resources.py already contains codenames, so we really could just do the lookup there and not use Launchpad.