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

{
    std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
    const CWallet* const pwallet = wallet.get();
    if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
        return NullUniValue;
    }
            RPCHelpMan{"listlabels",
                "\nReturns the list of all labels, or labels that are assigned to addresses with a specific purpose.\n",
                {
                    {"purpose", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, "Address purpose to list labels for ('send','receive'). An empty string is the same as not providing this argument."},
                },
                RPCResult{
                    RPCResult::Type::ARR, "", "",
                    {
                        {RPCResult::Type::STR, "label", "Label name"},
                    }
                },
                RPCExamples{
            "\nList all labels\n"
            + HelpExampleCli("listlabels", "") +
            "\nList labels that have receiving addresses\n"