Provide onchain benchmarks

[rdubois-crypto]

Current benchmarks are not consistent with on chain results. FCL is displayed as providing 370K tx, while on chain measurements are maximum 227K.

Also, what is state as average case seems to be average for WycheProof, while Maximum is indeed the average case (nominal case) for Tx

See practical on chain results here:

• https://goerli.basescan.org/tx/0xa40f2446479ec93fee8eeec263bc36d414d1337b96ae1fb1c248e56ec9610b3e (base)
• https://sepolia.etherscan.io/tx/0x8d9397c8b8424d3c8748f4e30b5a9f7ae24778c7d3602a11fabfadcefa1b6d6a (sepolia)

(click on see more to display gas used).