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) {
```
std::string strAddress, strKey, strValue;
            ssKey >> strAddress;
            ssKey >> strKey;
            ssValue >> strValue;
            pwallet->LoadDestData(DecodeDestination(strAddress), strKey, strValue);
        } else if (strType == DBKeys::HDCHAIN) {
            CHDChain chain;
            ssValue >> chain;
            pwallet->GetOrCreateLegacyScriptPubKeyMan()->LoadHDChain(chain);
        } else if (strType == DBKeys::OLD_KEY) {
            strErr = "Found unsupported 'wkey' record, try loading with version 0.18";
            return false;
        } else if (strType == DBKeys::ACTIVEEXTERNALSPK || strType == DBKeys::ACTIVEINTERNALSPK) {
            uint8_t type;
            ssKey >> type;
            uint256 id;
            ssValue >> id;
            bool internal = strType == DBKeys::ACTIVEINTERNALSPK;
            auto& spk_mans = internal ? wss.m_active_internal_spks : wss.m_active_external_spks;
            if (spk_mans.count(static_cast<OutputType>(type)) > 0) {
                strErr = "Multiple ScriptPubKeyMans specified for a single type";
                return false;
            }
            spk_mans[static_cast<OutputType>(type)] = id;
        } else if (strType == DBKeys::WALLETDESCRIPTOR) {
            uint256 id;
            ssKey >> id;
            WalletDescriptor desc;
            ssValue >> desc;
            if (wss.m_descriptor_caches.count(id) == 0) {