Leader has incorrect head

[GalRogozinski]

Description

Operators may have incorrect head due to proposers playing timing games or maybe the leader is faulty.
We could:

1. Delay attestation by 1.8-2 seconds
2. Require quorum agreement on head for first round.
3. (2) can be enhanced by firing round change early (@Roy-blox idea)

[GalRogozinski]

Brainstorm

1. If we see an empirical low delay (i.e 200 ms) for head events do we want to adjust our delay according to empirical data?

We need to worry about delays due to bandwidth congestion. So it sounds smart to delay as little as possible.
We need to gather more data?

References (TODO: find more resources)

See:
https://ethpandaops.io/posts/dencun-fork-analysis/

2. Do we want to validate head vote against local view?

At least for the first round, pending #82

3. We can create experiments with round change.