Alphabetically sort list of super users

[arnarg]

Fixes #288

Motivation

When specifying multiple roles in .Values.auth.superUsers the values are converted to a comma-separated list by piping the dict through values and join in helm templating, values however doesn't guarantee that the order of elements will be the same every time. Therefor it recommends also passing it through sortAlpha to sort the list alphabetically.

This is a problematic when .Values.broker.restartPodsOnConfigMapChange is enabled because the checksum of the configmap changes every time the list's order is changed, resulting in the statefulsets rolling out a new version of the pods.

Modifications

Pass list through sortAlpha.

Verifying this change

• [x] Make sure that the change passes the CI checks.