mask traceback which can be waived out
    
    addressing:
     Traceback (most recent call last):
       File "/usr/share/copr/coprs_frontend/coprs/views/stats_ns/stats_receiver.py", line 31, in logstash_handler
         handle_logstash(rcp.get_connection(), flask.request.json)
       File "/usr/share/copr/coprs_frontend/coprs/logic/stat_logic.py", line 104, in handle_logstash
         key = CHROOT_REPO_MD_DL_STAT_FMT.format(**ls_data)
     KeyError: 'copr_user'
     ERROR:coprs:'copr_user'