replace ci status badge (#4006)
replace ci status badge (#4006)

Signed-off-by: zhouqiang <f5e1e75d9d9f97d985236705b97ed039c008c7ea@pingcap.com>
BusyJay/tikv,c4pt0r/tikv,BusyJay/tikv,pingcap/tikv,BusyJay/tikv,BusyJay/tikv,pingcap/tikv