Correct SB project groups data type
Correct SB project groups data type

A handful of recent project additions included a "groups" key which
used a string instead of a list, and manage-projects dutifully
iterated over each element of these strings creating new
single-character project groups corresponding to them. Correct the
offending entries to be a list instead.

Manual cleanup will be required in StoryBoard's database once this
change merges.

Change-Id: Icbef648e9948e0fa636dd0d15039b6fc229541ca

openstack-infra/project-config,openstack-infra/project-config