The Rook and Ceph teams settled on using slashes to separate Rook
telemetry items into a hierarchy in https://github.com/rook/rook/pull/10254.
Rename the config-key used to `rook/version`, and create a `telemetry`
package to define the telemetry key constants.
Signed-off-by: Blaine Gardner <blaine.gardner@redhat.com>