Adding Sepolia network to network prefixes (#64)

Author: ryanml

src/prefix-for-network.ts

@@ -10,6 +10,9 @@ export = function getPrefixForNetwork(networkId: string): string | null {
     case 5: // goerli test net
       prefix = 'goerli.';
       break;
+    case 11155111: // sepolia test net
+      prefix = 'sepolia.';
+      break;
     default:
       prefix = null;
   }