Added summary generated event

[ameetpal]

What?

Emitting Summary Generated event

Why?

#3683

Checklist

• I have performed a self-review of my code.
• I have added tests for my changes.
• I have run linter locally (make lint) and all checks pass.
• I have run tests locally (make tests) and all tests pass.
• I have commented on my code, particularly in hard-to-understand areas.

Related PR(s)/Issue(s)

[CLAassistant]

All committers have signed the CLA.

[oleiade]

Hey @ameetpal 👋🏻

First and foremost, thanks a lot for taking the time and putting the effort into contributing to k6, we very much appreciate it 🙇🏻

We had a bit of a delay in our response as the team needed to discuss and synchronize on this topic. We reached the conclusion that we're rather open to reviewing and potentially merging this, with the specific caveat that we consider this internal event system experimental, and we might change/break it and its API in the future. Thus, if that's an acceptable prerequisite for you, we'll go ahead with the review indeed 👍🏻

PS: through our discussions, we outlined that this could potentially be a topic/issue/PR that you would be interested in @pablochacin 👀

[olegbespalov]

Hey @ameetpal

Thanks for your contribution!

From the code standpoint, it looks good. It could be merged. However, as @oleiade mentioned, we do consider this events API as experimental, and it could be changed in the following releases.

[ameetpal]

Hi @oleiade , @olegbespalov , we are fine with the condition and we can go ahead and merge this