The `dumpwallet` RPC command throws an error at the signet node and stops it.
~~This does not happen in mainnet or testnet, where the command worked successfully in my tests..~~
Originally this error was only happening on signet, but it also happened on testnet after it worked successfully for a while.

**Expected behavior**

The RPC `dumpwallet` command is expected to return a success message and create the dump file that contains the private keys.

**Actual behavior**

The command returns an error on client side (`bitcoin-cli`):
`error: timeout on transient error: Could not connect to the server 127.0.0.1:38332 (error code 1 - "EOF reached")
Make sure the bitcoind server is running and that you are connecting to the correct RPC port.`

And it throws an error at the signet node and stops it.

```
POTENTIAL DEADLOCK DETECTED
Previous lock order was:
  'cs_wallet' in wallet/wallet.cpp:2860 (in thread 'httpworker.1')
  (2) '::cs_main' in node/interfaces.cpp:687 (in thread 'httpworker.1')
  'm_node.mempool->cs' in node/interfaces.cpp:687 (in thread 'httpworker.1')
  'cs_wallet' in wallet/wallet.cpp:1204 (in thread 'httpworker.1')
  (1) 'cs_KeyStore' in script/signingprovider.cpp:165 (in thread 'httpworker.1')
Current lock order is:
  'wallet.cs_wallet' in wallet/rpcdump.cpp:743 (in thread 'httpworker.3')
  (1) 'spk_man.cs_KeyStore' in wallet/rpcdump.cpp:743 (in thread 'httpworker.3')
  (1) 'spk_man->cs_KeyStore' in wallet/wallet.cpp:2303 (in thread 'httpworker.3')
  (2) 'cs_main' in node/interfaces.cpp:493 (in thread 'httpworker.3')
Assertion failed: detected inconsistent lock order for 'cs_main' in node/interfaces.cpp:493 (in thread 'httpworker.3'), details in debug log.
Aborted (core dumped)
```

**To reproduce**

Start the node on signet mode:
`bitcoind -signet`

And dump an existing wallet:
`bitcoin-cli -signet -rpcwallet="legacy_wallet_01" dumpwallet "filename"`

**System information**

The bitcoin node was compiled from master (commit: `df2b5dadfb2dc21b05e5a60b71987fb5b96201f5`)
Ubuntu 20.04, 8 CPUs, 12 GiB RAM and SSD.

if (!crypter.Encrypt(_vMasterKey, kMasterKey.vchCryptedKey))
        return false;
    {
        LOCK(cs_waet);
        mapMasterKeys[++nMasterKeyMaxID] = kMasterKey;
        WaetBatch* encrypted_batch = new WaetBatch(GetDatabase());
        if (!encrypted_batch->TxnBegin()) {
            delete encrypted_batch;
            encrypted_batch = nuptr;
            return false;
        }
        encrypted_batch->WriteMasterKey(nMasterKeyMaxID, kMasterKey);
        const auto& spk_man_pair : m_spk_managers) {
            auto spk_man = spk_man_pair.second.get();
            if (!spk_man->Encrypt(_vMasterKey, encrypted_batch)) {
                encrypted_batch->TxnAbort();
                delete encrypted_batch;
                encrypted_batch = nuptr;
                // W
                // d
                assert(false);
            }
        }
        // E
        SetMinVersion(FEATURE_WALLETCRYPT, encrypted_batch);
        if (!encrypted_batch->TxnCommit()) {
            delete encrypted_batch;
            encrypted_batch = nuptr;
            // W
            // d