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).
{
    
    
    
    
    
    
    LOCK(cs_wallets);
    const fs::path& wallet_path = location.GetPath();
    fs::file_type path_type = fs::symlink_status(wallet_path).type();
    if (!(path_type == fs::file_not_found || path_type == fs::directory_file ||
          (path_type == fs::symlink_file && fs::is_directory(wallet_path)) ||
          (path_type == fs::regular_file && fs::path(location.GetName()).filename() == location.GetName()))) {
        error_string = strprintf(
              "Invalid -wallet path '%s'. -wallet path should point to a directory where wallet.dat and "
              "database/log.?????????? files can be stored, a location where such a directory could be created, "
              "or (for backwards compatibility) the name of an existing data file in -walletdir (%s)",
              location.GetName(), GetWalletDir());
        return false;
    }