Can't upgrade a k8s charm is /etc/os-release does not exist

[David]

Hello,

When upgrading a k8s charm that doesn't have /etc/os-release inside the application pod, the agent fails with panic saying:

failed: panic: cannot determine host series

If you want to reproduce it, you can use this charm:
https://github.com/davigar15/transmission-operator

I did this (https://github.com/davigar15/transmission-operator/blob/master/src/charm.py#L97) for the workaround, so you will need to comment this line (https://github.com/davigar15/transmission-operator/blob/master/src/charm.py#L204) in order to reproduce the problem

[Canonical Juju QA Bot (juju-qa-bot)]

This bug has not been updated in 2 years, so we're marking it Low importance. If you believe this is incorrect, please update the importance.