wallet: Disallow loading legacy wallets

Legacy wallets do not have the descriptors flag set. Don't load wallets
without the descriptors flag.

At the same time, we will no longer load BDB databases since they are
only used for legacy wallets.

src/wallet/test/util.h

@@ -5,8 +5,6 @@
 #ifndef BITCOIN_WALLET_TEST_UTIL_H
 #define BITCOIN_WALLET_TEST_UTIL_H
 
-#include <bitcoin-build-config.h> // IWYU pragma: keep
-
 #include <addresstype.h>
 #include <wallet/db.h>
 #include <wallet/scriptpubkeyman.h>
@@ -28,9 +26,6 @@ struct WalletContext;
 
 static const DatabaseFormat DATABASE_FORMATS[] = {
        DatabaseFormat::SQLITE,
-#ifdef USE_BDB
-       DatabaseFormat::BERKELEY,
-#endif
 };
 
 const std::string ADDRESS_BCRT1_UNSPENDABLE = "bcrt1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq3xueyj";