hardcoding erc20 token abi based on Oren's feedback

Author: cbrzn

src/arc.ts

@@ -42,7 +42,6 @@ import {
   Web3Client,
   Web3Provider
 } from './index'
-import { LATEST_ARC_VERSION } from './settings'
 
 const abis = require('./abis/abis.json')
 
@@ -631,9 +630,9 @@ export class Arc extends GraphNodeObserver {
   }
 
   public approveTokens(tokenAddress: Address, spender: Address, amount: BN) {
-    const erc20Abi = this.getABI({ abiName: 'ERC20Mock', version: LATEST_ARC_VERSION })
     const signer =  (this.web3 as JsonRpcProvider).getSigner(this.defaultAccount as any)
-    const tokenContract = new Contract(tokenAddress, erc20Abi, signer)
+    const abi = [{ "constant": false, "inputs": [ { "name": "_spender", "type": "address" }, { "name": "_value", "type": "uint256" } ], "name": "approve", "outputs": [ { "name": "", "type": "bool" } ], "payable": false, "stateMutability": "nonpayable", "type": "function" }]
+    const tokenContract = new Contract(tokenAddress, abi, signer)
 
     return this.sendTransaction({
       contract: tokenContract,

test/utils.ts

@@ -286,4 +286,4 @@ export function getContractAddressesFromMigration(environment: 'private' | 'rink
     }
   }
   return contracts
-}
+}