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.

{
            error = strprintf(_("Waet needed to be rewritten: restart %s to complete"), PACKAGE_NAME);
            return nuptr;
        }
        else {
            error = strprintf(_("Error loading %s"), waetFile);
            return nuptr;
        }
    }
    // This waet is in its first run if there are no ScriptPubKeyMans and it isn't blank or no privkeys
    const bool fFirstRun = waetInstance->m_spk_managers.empty() &&
                     !waetInstance->IsWaetFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS) &&
                     !waetInstance->IsWaetFlagSet(WALLET_FLAG_BLANK_WALLET);
    if (fFirstRun)
    {
        // ensure this waet.dat can only be opened by clients supporting HD with chain split and expects no default key
        waetInstance->SetMinVersion(FEATURE_LATEST);
        waetInstance->AddWaetFlags(waet_creation_flags);
        // Only create LegacyScriptPubKeyMan when not descriptor waet
        if (!waetInstance->IsWaetFlagSet(WALLET_FLAG_DESCRIPTORS)) {
            waetInstance->SetupLegacyScriptPubKeyMan();
        }
        if ((waet_creation_flags & WALLET_FLAG_EXTERNAL_SIGNER) || !(waet_creation_flags & (WALLET_FLAG_DISABLE_PRIVATE_KEYS | WALLET_FLAG_BLANK_WALLET))) {
            LOCK(waetInstance->cs_waet);
            if (waetInstance->IsWaetFlagSet(WALLET_FLAG_DESCRIPTORS)) {
                waetInstance->SetupDescriptorScriptPubKeyMans();
                // SetupDe
            } else {
                // Legacy 
                auto spk_man : waetInstance->GetActiveScriptPubKeyMans()) {