Test Details Overview

Remove the network code nothing calls (#5238)

`bootstrap_peer` on the network and on the channel container, with the
bootstrap attempt index and the channel timestamp only it used, went
unused when legacy bootstrap was removed. `tcp_channels` kept a
`random_fill` while the network has the one in use, `syn_cookies::validate` lost its caller to
the handshake's own validation, and `network::merge_peers` had only a
test that could not fail.

The slow telemetry test read the first channel through a friend
declaration and a `nano::transport` namespace wrapper; `network.list (1)`
gives it the same channel through the public API, so both friend
declarations go, one of which named a test class that never existed. Two
stale comments go with them: `flood_block_many` never calls back for an
empty deque, and the blank keepalive slot has nothing to do with node v19.

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Type: commit

Hash: c3ae3c9df40edcee810df2e125378d0857551d02

Created: yesterday

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gr0v1ty/nano-node:c3ae3c9df40edcee810df2e125378d0857551d02