Fix TypeError in exception handler

2 jobs for devel/wayland in 0 seconds (queued for 2112 minutes and 2 seconds)
Status Job ID Name Coverage
  Python2 Nose
failed #826677409
python2

 
  Python3 Nose
failed #826677411
python3

 
Name Stage Failure
failed
python2 Python2 Nose There has been a timeout failure or the job got stuck. Check your timeout limits or try again
No job log
failed
python3 Python3 Nose There has been a timeout failure or the job got stuck. Check your timeout limits or try again
No job log