While regtesting with [bitcoin-spock](https://github.com/msgilligan/bitcoin-spock) I noticed at some point the transaction creation via `sendtoaddress -> CreateTransaction()` fails, because the created transaction is larger than `MAX_STANDARD_TX_SIZE`.

During the process a lot of raw transactions are created, which have smallish outputs and when then using `sendtoaddress`, it appears to attempt to create a transaction that spends too many of those dust-ish outputs.

The transaction to create does not have many outputs, but it looks like it's caused by the coin selection, which selects too many inputs. Testing was done with a 0.9 branch, but on the first glimpse I believe this issue is as well be present in 0.10. If this is a known issue, and if there is already a guard against this behavior, I'd be happy about a hint.

Sorry in advance, I do not have a test script to reproduce this issue in an isolated manner. A potential fix would probably require to adjust the coin selection, so that it selects a combination of coins, which, in addition to the size of the rest of the transaction, is still smaller than the limit.

{
    static std::vector<OutputGroup> static_groups;
    static_groups.clear();
    for (auto& coin : available_coins) {
        static_groups.emplace_back();
        static_groups.back().Insert(coin,  0,  0,  false);
    }
    return static_groups;
}
inline std::vector<OutputGroup>& KnapsackGroupOutputs(const std::vector<COutput>& available_coins, CWallet& wallet, const CoinEligibilityFilter& filter)
{
    FastRandomContext rand{};
    CoinSelectionParams coin_selection_params{
        rand,
         0,
         0,
         CENT,
         CFeeRate(0),
         CFeeRate(0),
         CFeeRate(0),
         0,
         false,
    };
    static std::vector<OutputGroup> static_groups;
    static_groups = GroupOutputs(wallet, available_coins, coin_selection_params, filter, false);
    return static_groups;
}
BOOST_AUTO_TEST_CASE(bnb_search_test)