### Describe the issue
Because transaction malleability isn't that much of an issue lately, we've decided to let the wallet spend zero conf change. It has happened that we create a transaction just moments before a significant increase in (higher paying) transactions. Because of #9645, there is a chance that you end up with an unconfirmed chain of 24 child transactions. If you let the wallet produce a 25th child, it will return an error because the mempool won't accept it.  This is also problematic in the case we would like to cpfp the whole chain, because other nodes won't relay the transaction to the miners.

### Can you reliably reproduce the issue?
#### If so, please list the steps to reproduce below:
1. Predict an increase in transactions. (You need a crystal ball)
2. Create transaction
3. Create more transactions
4. ?
5. Profit

### Expected behaviour
Ideally it would stop if the chain is 24 transactions long, so one could try a cpfp transaction to compensate for the fees.

### Actual behaviour
It will create a transaction chain of 25 transaction, making it hard to have the whole chain confirmed in a certain time.

### What version of bitcoin-core are you using?
Official binary: 0.13.1
{
        std::vector<CTxOut> v_txouts(txouts.size());
        std::copy(txouts.begin(), txouts.end(), v_txouts.begin());
        return DummySignTx(txNew, v_txouts, coin_control);
    }
    bool DummySignTx(CMutableTransaction &txNew, const std::vector<CTxOut> &txouts, const CCoinControl* coin_control = nullptr) const;
    bool ImportScripts(const std::set<CScript> scripts, int64_t timestamp) EXCLUSIVE_LOCKS_REQUIRED(cs_wallet);
    bool ImportPrivKeys(const std::map<CKeyID, CKey>& privkey_map, const int64_t timestamp) EXCLUSIVE_LOCKS_REQUIRED(cs_wallet);
    bool ImportPubKeys(const std::vector<CKeyID>& ordered_pubkeys, const std::map<CKeyID, CPubKey>& pubkey_map, const std::map<CKeyID, std::pair<CPubKey, KeyOriginInfo>>& key_origins, const bool add_keypool, const bool internal, const int64_t timestamp) EXCLUSIVE_LOCKS_REQUIRED(cs_wallet);
    bool ImportScriptPubKeys(const std::string& label, const std::set<CScript>& script_pub_keys, const bool have_solving_data, const bool apply_label, const int64_t timestamp) EXCLUSIVE_LOCKS_REQUIRED(cs_wallet);
    CFeeRate m_pay_tx_fee{DEFAULT_PAY_TX_FEE};
    unsigned int m_confirm_target{DEFAULT_TX_CONFIRM_TARGET};
    /** Allow Coin Selection to pick unconfirmed UTXOs that were sent from our own wallet if it
     * cannot fund the transaction otherwise. */
    bool m_spend_zero_conf_change{DEFAULT_SPEND_ZEROCONF_CHANGE};
    bool m_signal_rbf{DEFAULT_WALLET_RBF};
    bool m_allow_fallback_fee{true}; 
    CFeeRate m_min_fee{DEFAULT_TRANSACTION_MINFEE}; 
    /**