Fix addresses_with_failover in cluster requests

[ianton-ru]

Changelog category (leave one):

• Bug Fix (user-visible misbehavior in an official stable release)

Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):

Fix filling addresses_with_failover with correct addresses

Documentation entry for user-facing changes

Bug made in #677
addresses_with_failover filled only with local addresses instead of all addresses.

Should fix flapped stateless test 02804_clusterAllReplicas_insert.

[arthurpassos]

Can you put the entire logic that lives inside this if statement in a separate method? IMHO, it is now slightly more complex and it deserves a named method. Perhaps something like:

/*
Shuffle shards_info to avoid picking only the first `max_hosts` hosts. Adjust addresses accordingly.
*/
static void constrainShardInfoAndAddressesToMaxHosts(ShardInfo & shard_info, Addresses & addresses)
{
        pcg64_fast gen{randomSeed()};
        std::shuffle(shards_info.begin(), shards_info.end(), gen);
        shards_info.resize(max_hosts);
        
        // shuffled_addresses must have the same ordering as shards_info, that's why the re-ordering is done manually instead of making a call to `std::shuffle`
        Addresses shuffled_addresses;
        for (auto & shard_info : shards_info)
        {
            shuffled_addresses.emplace_back(addresses[shard_info.shard_num - 1]);
            shard_info.shard_num = ++shard_num;
        }

         addresses.swap(shuffled_addresses);
}

[ianton-ru]

Move to separate method.