[addToken] USDf to MAINNET

[github-actions]

addToken

Note This is an automated PR

Submitted by @pleasingdonut

Closes #890

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Adding token USDf on network MAINNET

Address: 0xfa2b947eec368f42195f24f36d2af29f7c24cec2

Link to block explorer ↗︎

Description	Image
Original
Optimized

Reason

Our on-chain liquidity pools on - 
Curve: https://curve.fi/dex/ethereum/pools/factory-stable-ng-391/deposit/
Uniswap: https://app.uniswap.org/explore/tokens/ethereum/0xfa2b947eec368f42195f24f36d2af29f7c24cec2
Balancer: https://balancer.fi/pools/ethereum/v3/0x2412cF57C5d5aE1980BD2D30753d403FA194Fb4A

[github-actions]

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