[2.3-maintenance] Wait for build users when none are available

[flokli]

Backport of #3564 to 2.3-maintenance. One commit in the series (183dd28) was skipped due too many conflicts.

Motivation / Context

TVL is currently using a set of patches backported to 2.3. WIth the recent activity in 2.3-maintenance, we'd like to upstream these patches.

Priorities

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[Ericson2314]

@flokli Perhaps can you add a change log entry? Pity the original didn't have one.

[Ericson2314]

(It would be nice to figure out what fixed the macOS SIP issues and backport that too)

[flokli]

I looked, but we only have release notes for 2.3 itself, not for the to-be-planned point release, and it's a bit over my head to update the docbook pipeline for that.

Also, considering this doesn't include any functional changes - other than not exiting if busy, I'd argue it fixes a logic bug, rather than being a change in behaviour.

[flokli]

I'm offering to getting through the git log, and drafting some release notes for all of 2.3.17, once we cut it (#9244).

[Ericson2314]

@flokli Figuring that out when we actually cut the release sounds good to me :)

[flokli]

@Ericson2314 @edolstra is this good to merge like the three others, or anything that needs to be sorted out first?

[Ericson2314]

@flokli I just want to see CI pass.

[flokli]

Looks like macos passed this time, and the others got skipped 😆

[Ericson2314]

Good, that's progress. Restarted the Linux one.