Deploy and migrate to new version of EthereumFeeProxy - can't send fees to a multisig

[MantisClone]

Problems

1. Received report from hacker at ETHWarsaw that EtheruemFeeProxy transferWithReferenceAndFee() reverts if feeAmount is set to 0. The workaround was to set 1 wei fee. 👍

2. The EthereumFeeProxy transfers fees using .transfer() which has a hardcoded gas limit of 2300. Smart contract wallets like Safe have logic in their payable fallback() functions that require gas so .transfer() is not compatible with recipients that are smart contract wallets. Use .call() instead.

Definition of Done

• Investigate if EthereumFeeProxy allows 0 fee - Conclusion: It allows ✅ . See Implement test to show that EtheruemFeeProxy works with 0 fee #1218
• Fix EthereumFeeProxy to allow 0 fee
• Fix EthereumFeeProxy to use call() instead of transfer() for transferring fees
• Deploy new version on all networks where it already exists
• Update payment-processing and payment-detection packages
• Communicate new version to all builders.

Possible Follow-ups

• Consider importing interfaces instead of implementations.
• Consider changing paymentReference to bytes8 across all payment proxy contracts #1113
• Deploy new versions of any payment proxy contracts that depend on it.

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Migrated from Asana: https://app.asana.com/0/1203912381456855/1205450558867535/f

[MantisClone]

The EthereumFeeProxy allows you to send 0 fee ✅ see #1218