Attempting to load a wallet with an unknown descriptor causes a fatal error:

```
2022-09-06T01:51:06Z init message: Loading wallet…
2022-09-06T01:51:06Z [descriptor] Invalid descriptor: Can only have tr at top level: iostream error
2022-09-06T01:51:06Z [descriptor] Invalid descriptor: Can only have tr at top level: iostream error
2022-09-06T01:51:06Z [descriptor] Setting spkMan to active: id = 50e6032b4d1d62c020ebb6a4d0c8fafc6f01ea80f4d2a41c1a256086611636e9, type = legacy, internal = false
2022-09-06T01:51:06Z [descriptor] Setting spkMan to active: id = 7f709abbde61e8c253798375692bf41202e625ed74a65f9474d464be34fb2870, type = p2sh-segwit, internal = false
2022-09-06T01:51:06Z [descriptor] Setting spkMan to active: id = 2dc6c34099e0ca1235fc990a51042967ecbc8c8ac57062f964739cba2f451be8, type = bech32, internal = false
2022-09-06T01:51:06Z [descriptor] Setting spkMan to active: id = 8d3c63ea1ac9936e789713dc8bae857d328ff029ab9392e67c716752e9b11b0c, type = bech32m, internal = false
2022-09-06T01:51:06Z [descriptor] Releasing wallet
2022-09-06T01:51:06Z 

************************
EXCEPTION: St12out_of_range       
map::at       
bitcoin in Runaway exception       



************************
EXCEPTION: St12out_of_range       
map::at       
bitcoin in Runaway exception       

bitcoin-qt: ./checkqueue.h:204: CCheckQueue<CScriptCheck>::~CCheckQueue() [T = CScriptCheck]: Assertion `m_worker_threads.empty()' failed.
Aborted
```

> A fatal error occurred. Bitcoin Core can no longer continue safely and will quit.

To reproduce, a quick hack:

```c++
--- a/src/script/descriptor.cpp
+++ b/src/script/descriptor.cpp
@@ -1408,7 +1408,7 @@ std::unique_ptr<DescriptorImpl> ParseScript(uint32_t& key_exp_index, Span<const
         error = "Can only have addr() at top level";
         return nullptr;
     }
-    if (ctx == ParseScriptContext::TOP && Func("tr", expr)) {
+    if (ctx == ParseScriptContext::TOP && Func("trx", expr)) {
         auto arg = Expr(expr);
         auto internal_key = ParsePubkey(key_exp_index, arg, ParseScriptContext::P2TR, out, error);
         if (!internal_key) {
```
// Add tx to , because if it has change it's also ours,
    // otheise just for transaction history.
    CWalletTx* wtx = AddToWallet(tx, TxStateInactive{}, [&](CWalletTx& wtx, bool new_tx) {
        CHECK_NONFATAL(wtx.mapValue.empty());
        CHECK_NONFATAL(wtx.vOrderForm.empty());
        wtx.mapValue = stdmove(mapVal
        wtx.vOrderForm = stdmove(orderForm);
        wtx.fTimeReceivedIsTxTime = true;
        wtx.fFromMe = true;
        return true;
    });
    // wtx can only be null if the db write failed.
    if (!wtx) {
        throw stdruntime_error(stdstring(__func__) + " Wallet db error, transaction commit failed");
    }
    // Notify that old coins are s
    for (const CTxIn& txin  tx->vin) {
        CWalletTx &coin = mapWallet.at(txin.prevout.hash);
        coin.MarkDirty();
        NotifyTransactionChanged(coin.GetHash(), CT_UPDATED);
    }
    if (!fBroadcastTransactions) {
        // Don't submit tx to the mempool
        return;
    }
    stdstring err_string;
    if (!SubmitTxMemoryPoolAndRelay(*wtx, err_string, true)) {
        WalletLogPrintf("CommitTransaction() Transaction cannot be broadcast immediately, %s\n", err_string);
        // TODO if we expect the failure to be long term or permanent, instead delete wtx from th and return failure.
    }