Comment 1 for bug 1999673

Note: we have seen this type of issue elsewhere, and the fix is to add 'decode' to the data that we read.
example
https://review.opendev.org/c/starlingx/oidc-auth-armada-app/+/846174/4/oidc-auth-tools/oidcauthtools/oidcauthtools/oidc_auth.py

So changing the pipe_output method should be good enough

example
https://github.com/starlingx/monitoring/blob/f79dcc176f7c7c405731426bc242b3cfe48e1055/kube-memory/kube-memory/kube_memory/kube_memory.py#L184

changing:
 return last_popen[-1].communicate()[0]
to:
 return last_popen[-1].communicate()[0].decode()