PR description

extracted from #6968

• only disconnect "worst" peer if we have max peers.
• on incoming connection, compare the incoming peer to the current collection of peers and (if at max peers) disconnect whichever compares least favourably - in effect this will be the incoming peer if all our current peers are giving us good responses (reputation score), or it will be an existing peer if any are not giving good responses

example debug log (yes there is a TODO to remove this log)

{"@timestamp":"2024-04-19T00:53:31,297","level":"DEBUG","thread":"nioEventLoopGroup-3-9","class":"EthPeers","message":"comparing worstCurrentPeer PeerId: 0x024e106a70572288... PeerReputation score: 87, timeouts: {3=5}, useless: 0, validated? true, disconnected? false, client: erigon/v2.58.2-125509e4/linux-amd64/go1.21.8, [Connection with hashCode 1276176835 inboundInitiated? true initAt 1713481827797], enode://024e106a70572288701e97724610d120a682f69f24881eeee0ab1f6379646780d93daf11d9226593faf71deb699f24020dbecf801eb3d0da779ef2be641590fa@3.38.172.157:30304 with connectingPeer PeerId: 0x1ec3a5e247e616a3... PeerReputation score: 100, timeouts: {}, useless: 0, validated? true, disconnected? false, client: Nethermind/v1.25.4+20b10b35/linux-x64/dotnet8.0.2, [Connection with hashCode 1951644955 inboundInitiated? false initAt 1713488011205], enode://1ec3a5e247e616a347038b9c35a1328529bdf354408fe3c968433df542eb1b2a7c7d1b7b7d481a5b6465baac64877ee53e1396ddf43a3ad0f5f0adbaed659145@188.40.67.160:30303","throwable":""}

Thanks for sending a pull request! Have you done the following?

• Checked out our contribution guidelines?
• Considered documentation and added the doc-change-required label to this PR if updates are required.
• Considered the changelog and included an update if required.
• For database changes (e.g. KeyValueSegmentIdentifier) considered compatibility and performed forwards and backwards compatibility tests

Locally, you can run these tests to catch failures early:

• unit tests: ./gradlew build
• acceptance tests: ./gradlew acceptanceTest
• integration tests: ./gradlew integrationTest
• reference tests: ./gradlew ethereum:referenceTests:referenceTests