Add USDG metadata

[zpetersen-paxos]

Token Name: Global Dollar Symbol: USDG Token Address: 0xe343167631d89B6Ffc58B88d6b7fB0228795491D

Description: USDG is a fully-backed stablecoin issued by Paxos, always redeemable 1:1 for U.S. dollars. It is backed by U.S. dollar deposits, short-term U.S. Treasuries, and similar cash equivalents

Etherscan: https://etherscan.io/token/0xe343167631d89B6Ffc58B88d6b7fB0228795491D Coinmarketcap: https://coinmarketcap.com/currencies/global-dollar-usdg/ Website: https://globaldollar.com/