podman-systemd.unit.5: document /sbin/nologin accounts

[eriksjolund]

Add command:
sudo systemctl --machine username@ --user list-unit-files

Fixes: #27544

Checklist

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• Referenced issues using Fixes: #00000 in commit message (if applicable)
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Does this PR introduce a user-facing change?

None

[eriksjolund]

@hadmut Does it look okay?

[TomSweeneyRedHat]

@eriksjolund I've rerun the tests that look too unhappy for the changes in this particular PR

[Honny1]

LGTM, once @TomSweeneyRedHat's comments have been addressed.

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: eriksjolund, Honny1

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[packit-as-a-service]

[NON-BLOCKING] Packit jobs failed. @containers/packit-build please check. Everyone else, feel free to ignore.

[Honny1]

/packit retest-failed

[eriksjolund]

Are the failed tests related to this PR?
(I'm a little confused)

[baude]

Are the failed tests related to this PR? (I'm a little confused)

I dont think so, but to be sure, you are freshly rebased?

[eriksjolund]

I dont think so, but to be sure, you are freshly rebased?

I now rebased. Let's see if things change.

[mheon]

Good tip, didn't know this one.
/lgtm