e2e test for SGT

[blockchaindevsh]

[qizhou]

A list of manual tests is done here: https://perfect-amphibian-929.notion.site/SWC-Devnet-1282e493e88380648486d4961eb91a8d

To be more specific, we want to test

• SGT without native balance. The SGT balance difference should equal to tx cost.
• Full SGT payment with the native balance
• Partial SGT payment with native balance, where SGT becomes zero, and the rest of gas is paid by native. This ensures that as long as SGT + native balance >= tx cost, we will always accept the tx
• Insufficient gas with both SGT and native balance, i.e., SGT + native balance < tx cost

Besides these, we should also check whether the balances of the vaults (fee recipients) are expected.

[dajuguan]

Done in #125