Dynamically inject BBN env

[jrwbabylonlab]

Right now, we are hardcoding the BBN network in the code

cosmosChains={[
        {
          id: 2,
          name: "Babylon Devnet 4",
          type: "cosmos",
          network: "devnet-4",
          modularData: keplrRegistry,
          backendUrls: {
            rpcRrl: "https://rpc.devnet.babylonlabs.io",
          },
          logo: "https://raw.githubusercontent.com/chainapsis/keplr-chain-registry/main/images/bbn-dev/chain.png",
        },
      ]}

The scope of this ticket is to find a way to dynamically chose to use the right chain config based on process.env field value