`bitcoin-cli loadwallet "wallet.dat"` command causes bitcoind crash

log info:
```
bitcoind: wallet/db.cpp:236: BerkeleyEnvironment::VerifyResult BerkeleyEnvironment::Verify(const string&, BerkeleyEnvironment::recoverFunc_type, std::__cxx11::string&): Assertion `mapFileUseCount.count(strFile) == 0' failed.
Aborted (core dumped)
```

Bitcoin Core Daemon version `v0.17.0.0-ge1ed37edaedc85b8c3468bd9a726046344036243`

if (ret != 0)
            return ret;
        else if (datKey.get_data() == nullptr || datValue.get_data() == nullptr)
            return 99999;
        
        ssKey.SetType(SER_DISK);
        ssKey.clear();
        ssKey.write((char*)datKey.get_data(), datKey.get_size());
        ssValue.SetType(SER_DISK);
        ssValue.clear();
        ssValue.write((char*)datValue.get_data(), datValue.get_size());
        
        memory_cleanse(datKey.get_data(), datKey.get_size());
        memory_cleanse(datValue.get_data(), datValue.get_size());
        free(datKey.get_data());
        free(datValue.get_data());
        return 0;
    }
public:
    bool TxnBegin()
    {
        if (!pdb || activeTxn)
            return false;
        DbTxn* ptxn = env->TxnBegin();
        if (!ptxn)
            return false;
        activeTxn = ptxn;
        return true;
    }
    bool TxnCommit()