[OpenBit] Add support for B² Network Testnet

[meandhwh]

If this is your first time integrating, the following information is required

• Any other useful material so we can get to know you better: https://docs.bsquared.network/
• Github: https://github.com/b2network
• Faucet: https://www.bsquared.network/faucet/

If you want to integrate a chain, you would need to provide

• Name of the blockchain: B² Network Testnet
• Type of the blockchain: ZK Rollup, EVM
• Blockchain providers:
  https://b2-testnet.alt.technology
  https://rpc.ankr.com/b2_testnet
  https://testnet-rpc.bsquared.network
• Metadata of the blockchain (chainId, paraId, addressPrefix, symbol,...)
  Please check here: https://docs.paddlefi.com/chains/bsquare#bitlayer-mainnet-1
• Logo of the blockchain: https://www.figma.com/design/kx0dqXMzHmODOfWm9WMys0/02.OpenBit---Logo-Project?node-id=8-40&t=0cDdBQaHQ9AaJAvH-4
• Block explorers: https://testnet-explorer.bsquared.network/
• Native token: BTC
• Name of native token: Bitcoin Testnet
• Logo of the token: https://www.figma.com/design/kx0dqXMzHmODOfWm9WMys0/02.OpenBit---Logo-Project?node-id=2239-197&t=0cDdBQaHQ9AaJAvH-4
• Is your asset transferable? Yes
• PriceID: N/A

[bluezdot]

holders: https://testnet-explorer.bsquared.network/top-accounts