Correct previous Coverity static buffer fix. HTCONDOR-416
Correct previous Coverity static buffer fix. HTCONDOR-416

When using strncat(), the buffer can't be static. We need a fresh one on
the stack for every call.

htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor