Fixes "cinnamon-session-quit --logout --no-prompt --force" not working

[SimonBenito]

If you open command line and try:
cinnamon-session-quit --logout --no-prompt --force

Nothing happens. This suggested change corrects this behaviour.

Explanation of the error
The error happens because cinnamon-session-quit.py sends both flags (no-prompt + force) to cinnamon-session-binary, but the latter only handles one at a time. cinnamon-session-binary's debug output is "unknown logout mode option".

Explanation of the solution
In cinnamon-session-quit.py, if "--force" is issued, "--no-prompt" argument is ignored, as it is implied by the former. Thus, only the forceful flag is sent to cinnamon-session-binary

[SimonBenito]

Hey @clefebvre, is there any rules for submitting PR? I would like to develop a little more around reboot in cinnamon-session, including the ability to reboot to kexec and soft reboot. Let me know what you thing. Thanks!

[mtwebster]

I'd open a discussion regarding kexec/soft-reboot (https://github.com/orgs/linuxmint/discussions) - keeping in mind our intent is to provide the best 'default' behavior for the most users. We'd prefer to avoid complication that adds little value to this.

Thanks!