kv: deflake TestClientNotReady
kv: deflake TestClientNotReady

Fixes #5034.

vaibhavarora/cockroach,veteranlu/cockroach,maxlang/cockroach,sunya123/cockroach,sunya123/cockroach,nieyy/cockroach,arjun4084346/cockroach,paperstreet/cockroach,arjun4084346/cockroach,sunya123/cockroach,cuongdo/cockroach,veteranlu/cockroach,nieyy/cockroach,bg451/cockroach,vivekmenezes/cockroach,cockroachdb/cockroach,maxlang/cockroach,arjun4084346/cockroach,sunya123/cockroach,bg451/cockroach,cuongdo/cockroach,cuongdo/cockroach,petermattis/cockroach,petermattis/cockroach,arjun4084346/cockroach,bg451/cockroach,maxlang/cockroach,vaibhavarora/cockroach,maxlang/cockroach,arjun4084346/cockroach,vaibhavarora/cockroach,maxlang/cockroach,petermattis/cockroach,nieyy/cockroach,petermattis/cockroach,glycerine/cockroach,nieyy/cockroach,veteranlu/cockroach,nieyy/cockroach,vaibhavarora/cockroach,nieyy/cockroach,paperstreet/cockroach,paperstreet/cockroach,petermattis/cockroach,veteranlu/cockroach,vivekmenezes/cockroach,bg451/cockroach,glycerine/cockroach,cuongdo/cockroach,veteranlu/cockroach,cuongdo/cockroach,paperstreet/cockroach,veteranlu/cockroach,cockroachdb/cockroach,bg451/cockroach,cuongdo/cockroach,arjun4084346/cockroach,cuongdo/cockroach,paperstreet/cockroach,glycerine/cockroach,cockroachdb/cockroach,paperstreet/cockroach,glycerine/cockroach,vivekmenezes/cockroach,sunya123/cockroach,vaibhavarora/cockroach,maxlang/cockroach,cuongdo/cockroach,glycerine/cockroach,vivekmenezes/cockroach,vivekmenezes/cockroach,petermattis/cockroach,nieyy/cockroach,vaibhavarora/cockroach,cockroachdb/cockroach,maxlang/cockroach,glycerine/cockroach,veteranlu/cockroach,cockroachdb/cockroach,cockroachdb/cockroach,sunya123/cockroach,sunya123/cockroach,bg451/cockroach,nieyy/cockroach,sunya123/cockroach,vaibhavarora/cockroach,vivekmenezes/cockroach,petermattis/cockroach,vivekmenezes/cockroach,paperstreet/cockroach,maxlang/cockroach,glycerine/cockroach,vivekmenezes/cockroach,arjun4084346/cockroach,petermattis/cockroach,paperstreet/cockroach,cockroachdb/cockroach,cockroachdb/cockroach,glycerine/cockroach,vaibhavarora/cockroach,arjun4084346/cockroach,veteranlu/cockroach,bg451/cockroach