gedit test: fix gedit's application name

It was renamed into org.gnome.gedit in gedit 3.34.
2 jobs for master in 0 seconds (queued for 1112 minutes and 42 seconds)
Status Job ID Name Coverage
  Python2 Nose
failed #481852010
python2

 
  Python3 Nose
failed #481852012
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