libevent seems to have invaded `libbitcoin_common` via `url.cpp`

`url.cpp` is used only from `test/fuzz/string.cpp` and `wallet/rpcwallet.cpp`

libevent should only be required for bitcoind, bitcoin-cli and (due only to the hack of passing wallet names) bitcoin-qt

{
    const CChainParams& chainparams = Params();
    std::unique_ptr<CBlockTemplate> pblocktemplate = BlockAssembler(*m_node.mempool, chainparams).CreateNewBlock(scriptPubKey);
    CBlock& block = pblocktemplate->block;
    
    block.vtx.resize(1);
    for (const CMutableTransaction& tx : txns)
        block.vtx.push_back(MakeTransactionRef(tx));
    
    {
        LOCK(cs_main);
        unsigned int extraNonce = 0;
        IncrementExtraNonce(&block, ::ChainActive().Tip(), extraNonce);
    }
    while (!CheckProofOfWork(block.GetHash(), block.nBits, chainparams.GetConsensus())) ++block.nNonce;
    std::shared_ptr<const CBlock> shared_pblock = std::make_shared<const CBlock>(block);
    ProcessNewBlock(chainparams, shared_pblock, true, nullptr);
    CBlock result = block;
    return result;
}
TestChain100Setup::~TestChain100Setup()