Goal:

• We were recently made aware, that new keystone service types need to be reviewed and approved. New types need to follow a naming convention. "prometheus" as a service type, doesn't comply with the naming convention. We decided to rename it and instead go with "metric-storage"
• Related discussions:
  • https://redhat-internal.slack.com/archives/C01ED6VJ1SR/p1752770812360089
  • https://redhat-internal.slack.com/archives/C04ML02E1JQ/p1752826825421349
• Repository, where the name needs to be registered and where the naming convention is described: https://opendev.org/openstack/service-types-authority

Acceptance Criteria:

• The new "metric-storage" name is registered and all uses of the original "prometheus" type are changed to "metric-storage"