Use a real XML parser for issue generation.
Use a real XML parser for issue generation.

Should help us get labels for panics and timeouts (which used to work
but the fragile grep parsing broke recently).

Fixes #3493

glycerine/cockroach,arjun4084346/cockroach,maxlang/cockroach,cuongdo/cockroach,il9ue/cockroach,bg451/cockroach,vaibhavarora/cockroach,cockroachdb/cockroach,vaibhavarora/cockroach,vaibhavarora/cockroach,arjun4084346/cockroach,cuongdo/cockroach,nieyy/cockroach,paperstreet/cockroach,petermattis/cockroach,marcuswestin/cockroach,sunya123/cockroach,il9ue/cockroach,nieyy/cockroach,paperstreet/cockroach,bg451/cockroach,maxlang/cockroach,veteranlu/cockroach,paperstreet/cockroach,bg451/cockroach,cuongdo/cockroach,maxlang/cockroach,marcuswestin/cockroach,sunya123/cockroach,petermattis/cockroach,nieyy/cockroach,veteranlu/cockroach,bg451/cockroach,cockroachdb/cockroach,maxlang/cockroach,veteranlu/cockroach,petermattis/cockroach,vivekmenezes/cockroach,cuongdo/cockroach,vaibhavarora/cockroach,glycerine/cockroach,glycerine/cockroach,cuongdo/cockroach,arjun4084346/cockroach,petermattis/cockroach,maxlang/cockroach,glycerine/cockroach,il9ue/cockroach,arjun4084346/cockroach,maxlang/cockroach,marcuswestin/cockroach,il9ue/cockroach,il9ue/cockroach,paperstreet/cockroach,veteranlu/cockroach,vivekmenezes/cockroach,veteranlu/cockroach,sunya123/cockroach,arjun4084346/cockroach,vivekmenezes/cockroach,bg451/cockroach,nieyy/cockroach,vaibhavarora/cockroach,veteranlu/cockroach,cockroachdb/cockroach,sunya123/cockroach,nieyy/cockroach,marcuswestin/cockroach,marcuswestin/cockroach,maxlang/cockroach,vivekmenezes/cockroach,cockroachdb/cockroach,il9ue/cockroach,sunya123/cockroach,cuongdo/cockroach,veteranlu/cockroach,petermattis/cockroach,marcuswestin/cockroach,vivekmenezes/cockroach,glycerine/cockroach,glycerine/cockroach,arjun4084346/cockroach,nieyy/cockroach,sunya123/cockroach,maxlang/cockroach,cuongdo/cockroach,vaibhavarora/cockroach,sunya123/cockroach,paperstreet/cockroach,marcuswestin/cockroach,glycerine/cockroach,vivekmenezes/cockroach,paperstreet/cockroach,petermattis/cockroach,sunya123/cockroach,il9ue/cockroach,cockroachdb/cockroach,il9ue/cockroach,cockroachdb/cockroach,petermattis/cockroach,arjun4084346/cockroach,veteranlu/cockroach,arjun4084346/cockroach,vaibhavarora/cockroach,vivekmenezes/cockroach,nieyy/cockroach,glycerine/cockroach,paperstreet/cockroach,cockroachdb/cockroach,nieyy/cockroach,cuongdo/cockroach,cockroachdb/cockroach,bg451/cockroach,paperstreet/cockroach,petermattis/cockroach,vaibhavarora/cockroach,bg451/cockroach,marcuswestin/cockroach,vivekmenezes/cockroach