Improve the error information when using wrong type in signed extensions (ChargeAssetTxPayment)

[IkerAlus]

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Motivation

Once the Asset conversion pallet is live in Asset Hub runtimes, the signed extension ChargeAssetTxPayment allows to pay fees with an asset which has a liquidity pool created vs DOT by passing (optionally) the XCM location of the corresponding asset as a param of the signed extension. Before this feature was live, this worked by simply passing an integer as asset ID, Option(u32), in the mentioned signed extension. Hence if users were not aware of the change and they submit a transaction where the asset ID param of the ChargeAssetTxPayment signed extension is an integer it will fail during verification in the transaction pool and return the following error message from the node:

1002: Verification Error: Runtime error: Execution failed: Execution aborted due to trap: wasm trap: wasm `unreachable` instruction executed WASM backtrace: error while executing at wasm backtrace: 0: 0x3d6012 - <unknown>!rust_begin_unwind 1: 0x20ca - <unknown>!core::panicking::panic_fmt::h0d63004982a68afd 2: 0x32f7aa - <unknown>!TaggedTransactionQueue_validate_transaction: RuntimeApi, Execution failed: Execution aborted due to trap: wasm trap: wasm `unreachable` instruction executed\nWASM backtrace:\nerror while executing at wasm backtrace:\n 0: 0x3d6012 - <unknown>!rust_begin_unwind\n 1: 0x20ca - <unknown>!core::pa…

Several users encountered this issue when Polkadot Asset Hub was upgrade to 1.2 runtime, and it was not straightforward to find the root cause.

Request

Capture the wrong type usage during transaction verification in the transaction pool and return a relevant error message from the node.