Fix Etherscan maxFeePerGas post data key

[0xjc65eth]

Summary

Fixes the generated Etherscan provider output that still used maxFeePerGs instead of maxFeePerGas when normalizing transaction post data.

The TypeScript source already has the correct key, but the built ESM/CommonJS/dist artifacts still had the typo, so maxFeePerGas was not quantity-normalized before being sent through the Etherscan API path.

Closes #5080.

Testing

Ran small ESM and CommonJS smoke checks against _getTransactionPostData to confirm an EIP-1559 transaction with maxFeePerGas: 1000000000n serializes as:

maxFeePerGas = 0x3b9aca00
maxPriorityFeePerGas = 0x5f5e100

I also attempted npm run build-all, but the current checkout fails before this change with duplicate window / self declarations between lib.dom.d.ts and src.ts/crypto/crypto-browser.ts, so I kept this PR to the generated files that contain the typo.