Investigate where class/assembly cleanup failures are attached

[Youssef1313]

I think we blindly attach cleanup failures to the last test we have, even if that was an ignored test. A bit better behavior instead is to attach to the last non-ignored test. Still not ideal, but an improvement.

[thomhurst]

It'd be great to have nodes that aren't tests, and we can send an update message to represent these hooks and such.