
<!-- Describe the issue -->
Following commit 46004790588c24174a0bec49b540d158ce163ffd (@achow101), `decodepsbt` overstates the fee, apparently including both the `witness_utxo` and `non_witness_utxo` amounts in the inputs.

**Expected behavior**

The decoded fee should be the sum of the inputs, minus the sum of the outputs.

**Actual behavior**

The decoded fee is exactly twice the amount of the inputs, minus the sum of the outputs.

**To reproduce**

Build any PSBT using `createpsbt`, `walletprocesspsbt`, then decode it with `decodepsbt`. See the `fee` field in the JSON.

**System information**

I compiled myself from 5550fa5983ea59e7ccef6540b7ec49a1770fb3ca on Whonix 14.

Then I did `git revert 46004790588c24174a0bec49b540d158ce163ffd ` and the problem went away.

{
    RPCHelpMan{"sendrawtransaction",
                "\nSubmit a raw transaction (serialized, hex-encoded) to local node and network.\n"
                "\nNote that the transaction will be sent unconditionally to all peers, so using this\n"
                "for manual rebroadcast may degrade privacy by leaking the transaction's origin, as\n"
                "nodes will normally not rebroadcast non-wallet transactions already in their mempool.\n"
                "\nAlso see createrawtransaction and signrawtransactionwithkey calls.\n",
                {
                    {"hexstring", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "The hex string of the raw transaction"},
                    {"maxfeerate", RPCArg::Type::AMOUNT,  FormatMoney(DEFAULT_MAX_RAW_TX_FEE_RATE.GetFeePerK()),
                        "Reject transactions whose fee rate is higher than the specified value, expressed in " + CURRENCY_UNIT +
                            "/kB.\nSet to 0 to accept any fee rate.\n"},
                },
                RPCResult{
                    RPCResult::Type::STR_HEX, "", "The transaction hash in hex"
                },
                RPCExamples{
            "\nCreate a transaction\n"
            + HelpExampleCli("createrawtransaction", "\"[{\\\"txid\\\" : \\\"mytxid\\\",\\\"vout\\\":0}]\" \"{\\\"myaddress\\\":0.01}\"") +
            "Sign the transaction, and get back the hex\n"
            + HelpExampleCli("signrawtransactionwithwallet", "\"myhex\"") +