process: make sure we don't read past GTop.get_proc_argv's return value's length

If a process doesn't have any arguments passed to it its argv will only
have a size of 1 - its own name

fixes #80
2 jobs for fix-80 in 20 minutes and 2 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Build
passed #898030
build

00:15:43

 
  Test
passed #898031
flatpak
flatpak

00:04:18