Remove peer sampling code

[jimmygchen]

Issue Addressed

Peer sampling has been completely removed from the spec. This PR removes our partial implementation from the codebase.
ethereum/consensus-specs#4393

[pawanjay176]

LGTM, love removing code.
Just want to run a sync test to make sure nothing depended on sampling

[jimmygchen]

LGTM, love removing code. Just want to run a sync test to make sure nothing depended on sampling

Good idea, triggered one now

[jimmygchen]

@pawanjay176 sync tests are working - except for Fulu backfill for superdnodes which still needs retry implemented in your PR. I'll go ahead and merge this one.

[mergify]

This pull request has been removed from the queue for the following reason: checks failed.

The merge conditions cannot be satisfied due to failing checks:

• ☑️ local-testnet-success

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