refactor: when testing deferral, don't observe life cycle events

[dimaqq]

Pulled out from the OTEL branch.
Since life cycle events can't be deferred anyway, let's not observe them in these tests.
I hope this makes the tests more focused, and perhaps easier to maintain.

Inspired by #1589

[tonyandrewmeyer]

The change looks good to me - but the PR title seems wrong. This isn't ignoring lifecycle events (which would be a bad change I think), this is making the test code do the same thing but be more maintainable.

[dimaqq]

I've rewritten the PR title and description.

I think what motivated my change was that I was confused by "defer by count" in the first place.

It felt like a total coincidence that CollectStatus was not deferred.

[tonyandrewmeyer]

I've rewritten the PR title and description.

I think what motivated my change was that I was confused by "defer by count" in the first place.

It felt like a total coincidence that CollectStatus was not deferred.

Sorry, this is mostly my bad. I somehow overlooked before the new if statement, so I was only seeing the change in how the observed events are extracted and that didn't line up with the title.

However, it's not really a coincidence, it's careful manipulation of the counts so that the lifecycle ones aren't deferred (the test would error if that happened, since defer raises).

I don't think the "defer by count" is great for maintainability - this change probably does improve things a bit so that when figuring out counts you can skip over the lifecycle ones.