message: Add blockchair as btc block explorer
  Ticket:BG-22317
diff: @@ -15,6 +15,7 @@ interface EnvironmentTemplate {
  signingAddress: string;
  serverXpub: string;
  hsmXpub: string;
  + blockchairBaseUrl: string;
  btcExplorerBaseUrl: string;
  bchExplorerBaseUrl: string;
  bsvExplorerBaseUrl?: string;
  @@ -91,6 +92,7 @@ const mainnetBase: EnvironmentTemplate = {
  signingAddress: '1BitGo3gxRZ6mQSEH52dvCKSUgVCAH4Rja',
  serverXpub: hardcodedPublicKeys.serverXpub.prod,
  hsmXpub: hardcodedPublicKeys.hsmXpub.prod,
  + blockchairBaseUrl: 'https://api.blockchair.com/bitcoin',
  btcExplorerBaseUrl: 'https://blockstream.info/api',
  bchExplorerBaseUrl: 'https://blockdozer.com/insight-api',
  btgExplorerBaseUrl: 'https://btgexplorer.com/api',
  @@ -115,6 +117,7 @@ const testnetBase: EnvironmentTemplate = {
  signingAddress: 'msignBdFXteehDEgB6DNm7npRt7AcEZJP3',
  serverXpub: hardcodedPublicKeys.serverXpub.test,
  hsmXpub: hardcodedPublicKeys.hsmXpub.test,
  + blockchairBaseUrl: 'https://api.blockchair.com/bitcoin/testnet',
  btcExplorerBaseUrl: 'https://blockstream.info/testnet/api',
  bchExplorerBaseUrl: 'https://test-bch-insight.bitpay.com/api',
  etherscanBaseUrl: 'https://kovan.etherscan.io',
  @@ -168,6 +171,7 @@ export const Environments: Environments = {
  }),
  mock: Object.assign({}, devBase, {
  uri: 'https://bitgo.fakeurl',
  + blockchairBaseUrl: 'https://api.blockchair.fakeurl/bitcoin/testnet',
  btcExplorerBaseUrl: 'https://blockstream.fakeurl/testnet/api',
  bchExplorerBaseUrl: 'https://test-bch-insight.bitpay.fakeurl/api',
  stellarFederationServerUrl: 'https://bitgo.fakeurl/api/v2/txlm/federation',
  @@ -203,6 +207,10 @@ export const Environments: Environments = {
  network: process.env.BITGO_CUSTOM_BITCOIN_NETWORK as V1Network,
  rmgNetwork: process.env.BITGO_CUSTOM_RMG_NETWORK as V1RmgNetwork,
  hsmXpub: hardcodedPublicKeys.hsmXpub.dev,
  + blockchairBaseUrl:
  + process.env.BITGO_CUSTOM_BITCOIN_NETWORK !== 'bitcoin'
  + ? 'https://api.blockchair.com/bitcoin/testnet'
  + : 'https://api.blockchair.com/bitcoin',
  btcExplorerBaseUrl:
  process.env.BITGO_CUSTOM_BITCOIN_NETWORK !== 'bitcoin'
  ? 'https://blockstream.info/testnet/api'
  