Incorrect charged_fee on some sapphire transactions

[lukaw3d]

From slack:
@matevz noticed some transactions drain balance less than the displayed Fee in explorer shows

https://explorer.oasis.io/testnet/sapphire/tx/509ea6b6687ab83a791360600eb7f53be15a071aac72510adb374739fdb945e2

Tx:
Fee 0.23 TEST

Event
To: Fee Accumulator
Amount 0.0125194 TEST

Frontend displays charged_fee from backend https://testnet.nexus.oasis.io/v1/sapphire/transactions/509ea6b6687ab83a791360600eb7f53be15a071aac72510adb374739fdb945e2

"charged_fee": "226521700000000000"

[lukaw3d]

This transaction doesn't have tx_eth_hash, so this SQL is wrong

nexus/storage/client/queries/queries.go

Lines 553 to 556 in 2d9e786

	CASE
	WHEN txs.tx_eth_hash IS NULL THEN txs.fee
	ELSE COALESCE(FLOOR(txs.fee / NULLIF(txs.gas_limit, 0)) * txs.gas_used, 0)
	END AS charged_fee,