Did you do?
sudo apt-get update
sudo apt-get upgrade
then:
cd frappe-bench
bench update
then you got the above message.
NEXT step is:
bench reinstall
then
bench update
Hope this helps.
Only one is not perfect, I got this message in the end of the update:
frappe-bench-node-socketio: ERROR (abnormal termination)
I get this message in different production and develop servers by now
refer: