Add label `type` to gitlab_database_rows metrics for `groups`
The metric groups
in gitlab_database_rows
use the database table namespaces
. Namespaces can be User and Project, these are distinguishable by the column type
. I also suggest to change the label from groups
to namespaces
.
Suggested change in: https://gitlab.com/gitlab-org/gitlab-exporter/-/merge_requests/181