A0-3094: Validators network details rpc call

[ggawryal]

Description

Adding an RPC call to get network details of validators. This only pulls and caches network data that was previously observed by a node, without modifying or adding any new information flow between nodes in the network.

Related PRs: #1448 #1449

RPC query output on local network

curl -H "Content-Type: application/json" -d '{"id":1, "jsonrpc":"2.0", "method": "alephNode_unstable_validatorNetworkInfo", "params": []}' http://localhost:9948/

{
  "jsonrpc": "2.0",
  "result": {
      "5F4H97f7nQovyrbiq4ZetaaviNwThSVcFobcA5aGab6167dK": {
          "session": 1,
          "network_level_address": "127.0.0.1:30346",
          "validator_network_peer_id": "5CwWuuXMCvcSC7hqeMdFSfNFzVGXCAtdSGAMjwV1nLwaqtqE"
      },
      "5GBNeWRhZc2jXu7D55rBimKYDk8PGk8itRYFTPfC8RJLKG5o": {
          "session": 1,
          "network_level_address": "127.0.0.1:30344",
          "validator_network_peer_id": "5H7yZo8EzYkSsZn7MgC4f9vaVYQLgNaS4kEZ29Q7WtiYMVF8"
      },
      "5Dfis6XL8J2P6JHUnUtArnFWndn62SydeP8ee8sG2ky9nfm9": {
          "session": 1,
          "network_level_address": "127.0.0.1:30345",
          "validator_network_peer_id": "5HZFGbT6tsY2iV2YT927wnN4q2TxmPT67SUJE99TqGQsjpGV"
      },
      "5D34dL5prEUaGNQtPPZ3yN5Y6BnkfXunKXXz6fo7ZJbLwRRH": {
          "session": 1,
          "network_level_address": "127.0.0.1:30343",
          "validator_network_peer_id": "5E1YcJyx4u3kQ4UiRPgPXPSvb2vbcCR2DsxS927GM6x8wz85"
      }
  },
  "id": 1
}                        

Has been run also on testnet, slowly collects network details for authorities in each session (without AccountId because of the old runtime version).

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)

Checklist:

• I have created new documentation

[DamianStraszak]

Very nice!

[kostekIV]

gj