Fix package install output when a no-op #19481

[lukester1975]

Changelog: Fix: Display packages even when a system package manager install is a no-op.
Docs: Omit

Closes #19481

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[memsharded]

Thanks for your contribution @lukester1975 !

Ideally, it would be the best to cover this with some check in some unit tests, but I have checked it and it is not trivial, so don't worry about it. I think it can be merged, it is quite straightforward fix.

[memsharded]

Merged, it will be in next 2.25, thanks!