Opening two of the same wallet (tested in v0.18.0 of bitcoin-qt 64 bit) will cause a database collision, and will crash the program.

`[marshall@likon] {21:21} [~] $ bitcoin-0.18.0/bin/bitcoin-qt `
`terminate called after throwing an instance of 'std::runtime_error'  what():  BerkeleyBatch: Can't open database 8204388-wallet.dat (duplicates fileid 8b1c090000000800e25686350000000000000000 from 1352491-wallet.dat)`
`Aborted (core dumped)`

I have been able to reproduce the issue by importing two of the same wallet (with different filenames).
{
    
    bool create_blank = (wallet_creation_flags & WALLET_FLAG_BLANK_WALLET);
    
    if (!passphrase.empty()) {
        wallet_creation_flags |= WALLET_FLAG_BLANK_WALLET;
    }
    
    WalletLocation location(name);
    if (location.Exists()) {
        error = "Wallet " + location.GetName() + " already exists.";
        return WalletCreationStatus::CREATION_FAILED;
    }
    
    if (!CWallet::Verify(chain, location, false, error, warnings)) {
        error = "Wallet file verification failed: " + error;
        return WalletCreationStatus::CREATION_FAILED;
    }
    
    if (!passphrase.empty() && (wallet_creation_flags & WALLET_FLAG_DISABLE_PRIVATE_KEYS)) {
        error = "Passphrase provided but private keys are disabled. A passphrase is only used to encrypt private keys, so cannot be used for wallets with private keys disabled.";
        return WalletCreationStatus::CREATION_FAILED;
    }
    
    std::shared_ptr<CWallet> wallet = CWallet::CreateWalletFromFile(chain, location, error, warnings, wallet_creation_flags);
    if (!wallet) {
        error = "Wallet creation failed: " + error;
        return WalletCreationStatus::CREATION_FAILED;
    }