Backport: stein
In the Stein release, cloudkitty switched the default storage backend
from sqlalchemy to influxdb. In kolla-ansible stein configuration, we
did not explicitly set the storage backend, and so we automatically
picked up this change. However, prior to
https://review.opendev.org/#/c/615928/ we did not have full support for
InfluxDB as a storage backend, and so this has broken the Rocky-Stein
upgrade (https://bugs.launchpad.net/kolla-ansible/+bug/1838641), which
fails with this during the DB sync:
ERROR cloudkitty InfluxDBClientError: get_list_retention_policies()
requires a database as a parameter or the client to be using a database
This change synchronises our default with cloudkitty's (influxdb), and
also provides an upgrade transition to create the influxdb database.
We also move the cloudkitty_storage_backend variable to
group_vars/all.yml, since it is used to determine whether to enable
influxdb.
Finally, the section name in cloudkitty.conf was incorrect - it was
storage_influx, but should be storage_influxdb.
Change-Id: I71f2ed11bd06f58e141d222e2709835b7ddb2c71
Closes-Bug: #1838641
27f4876eed