I have 2 legacy wallets and on both if I run `upgradewallet` it will cause bitcoin core to crash. This should just return me an error string

Currenl result from `getwalletinfo`:
```
{
  "walletname": "Wallet",
  "walletversion": 169900,
  "format": "bdb",
  "balance": 0.00000000,
  "unconfirmed_balance": 0.00000000,
  "immature_balance": 0.00000000,
  "txcount": 80,
  "keypoololdest": 1613078825,
  "keypoolsize": 941,
  "keypoolsize_hd_internal": 941,
  "paytxfee": 0.00000000,
  "private_keys_enabled": false,
  "avoid_reuse": true,
  "scanning": false,
  "descriptors": false
}
```
{
    LOCK(cs_desc_man);
    if (!m_map_crypted_keys.empty()) {
        return false;
    }
    for (const KeyMap::value_type& key_in : m_map_keys)
    {
        const CKey &key = key_in.second;
        CPubKey pubkey = key.GetPubKey();
        CKeyingMaterial secret(key.begin(), key.end());
        std::vector<unsigned char> crypted_secret;
        if (!EncryptSecret(master_key, secret, pubkey.GetHash(), crypted_secret)) {
            return false;
        }
        m_map_crypted_keys[pubkey.GetID()] = make_pair(pubkey, crypted_secret);
        batch->WriteCryptedDescriptorKey(GetID(), pubkey, crypted_secret);
    }
    m_map_keys.clear();
    return true;
}
bool DescriptorScriptPubKeyMan::GetReservedDestination(const OutputType type, bool internal, CTxDestination& address, int64_t& index, CKeyPool& keypool, bilingual_str& error)
{
    LOCK(cs_desc_man);
    bool result = GetNewDestination(type, address, error);
    index = m_wallet_descriptor.next_index - 1;
    return result;
}
void DescriptorScriptPubKeyMan::ReturnDestination(int64_t index, bool internal, const CTxDestination& addr)