add a new contract for bsc so we can verify code

Author: joshstevens19

src/multicall.ts

@@ -511,7 +511,7 @@ export class Multicall {
       case Networks.goerli:
         return '0x5BA1e12693Dc8F9c48aAD8770482f4739bEeD696';
       case Networks.bsc:
-        return '0xAf379C844f87A7b47EE6fe5E4a9720988EaEA0AF';
+        return '0xC50F4c1E81c873B2204D7eFf7069Ffec6Fbe136D';
       case Networks.xdai:
         return '0x2325b72990D81892E0e09cdE5C80DD221F147F8B';
       case Networks.mumbai: