feat: fractional mainnet migration

This PR refactors mainnet and development migrations to reflect changes introduced in https://github.com/ubiquity/ubiquity-dollar/pull/922

The main changes are: 1) Curve's Governance-WETH crypto pool:

mainnet: use already deployed contract at https://etherscan.io/address/0xacdc85afcd8b83eb171affcbe29fad204f6ae45c
anvil/testnet: deploy a mock from scratch 2) Chainlink price feed for ETH/USD pair:
mainnet: use already deployed price feed at https://etherscan.io/address/0x5f4eC3Df9cbd43714FE2740f5E3616155c5b8419
anvil/testnet: deploy a mock price feed from scratch 3) Small updates like setting collateral ratio to 95% from start, calling some necessary setters, etc...

P.S. All tests are passed for anvil instance forked from mainnet in this test file

ubiquity / ubiquity-dollar