Re-evaluate `llnode`in the tools tier-list

[RafaelGSS]

As discussed in #533. I'm adding this item to the agenda to evaluate its tier or remove it from the tier-list document.

[tony-go]

We tried to look at this item during today's meeting (#552).

It seems that we didn't have enough insights to status on this. So we thought that, maybe @mmarchini you could share you thoughts?

As the request is probably a bit board, we'd like to know:

• Maybe do you remember why the tier 2 was targeted? (list)
• What about the current documentation state?
• How could we have regular testing in Node.js CI?

Sorry if I ask too many things 🙈

See you 👋

[tony-go]

PR created!

We should keep this issue open until @gireeshpunathil has feedback from llnode contributor.

[RafaelGSS]

Closing in favor of: nodejs/node#43289