[prebuild] stuck in PENDING if image build fails (due to error in dockerfile)

[AlexTugarev]

Bug description

see #13204 (comment) for context. while the linked issue is a dupe, this follow up seems to be a valid in itself.

if the image build exits with error code > 0, e.g. failure during apt-get install zzz, the workspace instance is marked as stopped, but the prebuild workspace won't be marked as failed. this means the state of the prebuild remains "PENDING" indefinitely.

we've the bridge in place to cleanup workspace instances (and derived resources) periodically, but in this case the WSI is stopped properly already. I think it wont cover this state.

cc. @geropl, please correct me if I'm wrong.

Steps to reproduce

see #13204

Workspace affected

No response

Expected behavior

prebuild workspace should be marked as failed.

this is quite important, because due to the lack of persisted image build logs, it's completely unclear what the status of a prebuild is.

Example repository

No response

Anything else?

No response

[geropl]

@geropl, please correct me if I'm wrong.

@AlexTugarev Correct. If we stop the instance, the contract is to also stop all derived prebuilds. That contract is broken 💯 .

[AlexTugarev]

The fix is buried in #13113. Going to extract it later on.