### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current behaviour

crash

### Expected behaviour

no crash

### Steps to reproduce

* Compile 79e8247ddb166f9b980f40249b7372a502402a4d
* Type `migratewallet`

### Relevant log output

```
wallet/scriptpubkeyman.cpp:1915: std::optional<MigrationData> wallet::LegacyScriptPubKeyMan::MigrateToDescriptor(): Assertion `IsMine(desc_spk) != ISMINE_NO' failed.
Aborted (core dumped)
```


### How did you obtain Bitcoin Core

Compiled from source

### What version of Bitcoin Core are you using?

current master

### Operating system and version

Linux

### Machine specifications

_No response_
{
    AssertLockHeld(cs_desc_man);
    std::unique_ptr<FlatSigningProvider> out_keys = std::make_unique<FlatSigningProvider>();
    
    auto it = m_map_signing_providers.find(index);
    if (it != m_map_signing_providers.end()) {
        out_keys->Merge(FlatSigningProvider{it->second});
    } else {
        
        std::vector<CScript> scripts_temp;
        if (!m_wallet_descriptor.descriptor->ExpandFromCache(index, m_wallet_descriptor.cache, scripts_temp, *out_keys)) return nullptr;
        
        m_map_signing_providers[index] = *out_keys;
    }
    if (HavePrivateKeys() && include_private) {
        FlatSigningProvider master_provider;
        master_provider.keys = GetKeys();
        m_wallet_descriptor.descriptor->ExpandPrivate(index, master_provider, *out_keys);
    }
    return out_keys;
}
std::unique_ptr<SigningProvider> DescriptorScriptPubKeyMan::GetSolvingProvider(const CScript& script) const
{
    return GetSigningProvider(script, false);
}
bool DescriptorScriptPubKeyMan::CanProvide(const CScript& script, SignatureData& sigdata)
{
    return IsMine(script);
}
bool DescriptorScriptPubKeyMan::SignTransaction(CMutableTransaction& tx, const std::map<COutPoint, Coin>& coins, int sighash, std::map<int, bilingual_str>& input_errors) const