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_storage.IsLocked() || m_storage.IsWalletFlagSet(WALLET_FLAG_LAST_HARDENED_XPUB_CACHED)) {
        return;
    }
    
    if (m_wallet_descriptor.cache.GetCachedLastHardenedExtPubKeys().size() > 0) {
        return;
    }
    
    FlatSigningProvider provider;
    provider.keys = GetKeys();
    FlatSigningProvider out_keys;
    std::vector<CScript> scripts_temp;
    DescriptorCache temp_cache;
    if (!m_wallet_descriptor.descriptor->Expand(0, provider, scripts_temp, out_keys, &temp_cache)){
        throw std::runtime_error("Unable to expand descriptor");
    }
    
    DescriptorCache diff = m_wallet_descriptor.cache.MergeAndDiff(temp_cache);
    if (!WalletBatch(m_storage.GetDatabase()).WriteDescriptorCacheItems(GetID(), diff)) {
        throw std::runtime_error(std::string(__func__) + ": writing cache items failed");
    }
}
void DescriptorScriptPubKeyMan::UpdateWalletDescriptor(WalletDescriptor& descriptor)