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);
    assert(m_storage.IsWalletFlagSet(WALLET_FLAG_DESCRIPTORS));
    
    if (m_wallet_descriptor.descriptor) {
        return false;
    }
    int64_t creation_time = GetTime();
    std::string xpub = EncodeExtPubKey(master_key.Neuter());
    
    std::string desc_prefix;
    std::string desc_suffix = "/*)";
    switch (addr_type) {
    case OutputType::LEGACY: {
        desc_prefix = "pkh(" + xpub + "/44'";
        break;
    }
    case OutputType::P2SH_SEGWIT: {
        desc_prefix = "sh(wpkh(" + xpub + "/49'";
        desc_suffix += ")";
        break;
    }
    case OutputType::BECH32: {
        desc_prefix = "wpkh(" + xpub + "/84'";
        break;
    }
    case OutputType::BECH32M: {
        desc_prefix = "tr(" + xpub  + "/86'";
        break;
    }