fix(deployment): simplify probes command to reduce false positives

[radicand]

In some (rare - one documented in #134) instances, the deployment liveness/readiness probes may time out while running. Investigation into this seems to be that the supervisorctl status command returned the right information, but somewhere in the double grep chaining the command could hang.

The good news is there is no need for the double grepping. supervisorctl status will return an exit code of 0 when all services provided as arguments are in the RUNNING state, which is what we're intending to check anyway. If any services are not running, supervisorctl status returns a non-zero exit code which k8s will interpret as a probe failure.

This cleaner method is actually more reliable regardless, as it could be the case in the previous implementation that the probe would not fail if one of the key services was not running, but any one of the specified services was.

Finally, note that in this pull request I only included the baseline services that all installations use - there is an opportunity to conditionally include more services in the check based on what the user has chosen to enable in their values.yaml.

[radicand]

Note the PR now has been adapted for the dms-healthcheck script, but until it lands the chart-testing steps will fail. Will revisit once a new release is cut to target against.

[cfis]

This looks good to me. We can merge once a new version of docker-mailserver is released. @polarathene any thoughts on that?

[polarathene]

@polarathene any thoughts on that?

Release is blocked on me finding time to review the Debian 13 + Dovecot 2.4 upgrade PR 😓

Unfortunately DMS is low on maintainers, and PRs like that one aren't as breezy to review confidently 😅 I'll try to fit some time towards resuming my review this week if I can.