 metrics: keep unit consistent with tikv (#3567)
 metrics: keep unit consistent with tikv (#3567)

* update

Signed-off-by: lhy1024 <admin@liudos.us>

* empty commit

Signed-off-by: lhy1024 <admin@liudos.us>

Co-authored-by: Ti Chi Robot <72214b26dd6f24c8c411751e1f8e05856122286e@users.noreply.github.com>
pingcap/pd,pingcap/pd