Is your feature request related to a problem?

I'm trying to run cli on raspberry where I have no x11 environment, so I have not installed python3-pyqt5.
When I run the command ./cli/urh_cli.py --help

Traceback (most recent call last):
  File "/home/pi/dev/urh/src/urh/./cli/urh_cli.py", line 29, in <module>
    from urh.util import util
  File "/home/pi/dev/urh/src/urh/util/util.py", line 12, in <module>
    from PyQt5.QtCore import Qt
ModuleNotFoundError: No module named 'PyQt5'

Describe the solution you'd like

I'd like run cli without pyqt5 dependencies, which are useless in headless environment.