fix: remove json file to fix json import error (#527)

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## Description
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Fix error import json file using core utils functions

## Related Issue Or Context
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issue first -->
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Closes: #<issue>

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- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation

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packages/core/src/multiCallAbi.ts

@@ -0,0 +1,86 @@
+export const MulticallAbi = [
+  {
+    constant: true,
+    inputs: [],
+    name: 'getCurrentBlockTimestamp',
+    outputs: [{ name: 'timestamp', type: 'uint256' }],
+    payable: false,
+    stateMutability: 'view',
+    type: 'function',
+  },
+  {
+    constant: false,
+    inputs: [
+      {
+        components: [
+          { name: 'target', type: 'address' },
+          { name: 'callData', type: 'bytes' },
+        ],
+        name: 'calls',
+        type: 'tuple[]',
+      },
+    ],
+    name: 'aggregate',
+    outputs: [
+      { name: 'blockNumber', type: 'uint256' },
+      { name: 'returnData', type: 'bytes[]' },
+    ],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+  },
+  {
+    constant: true,
+    inputs: [],
+    name: 'getLastBlockHash',
+    outputs: [{ name: 'blockHash', type: 'bytes32' }],
+    payable: false,
+    stateMutability: 'view',
+    type: 'function',
+  },
+  {
+    constant: true,
+    inputs: [{ name: 'addr', type: 'address' }],
+    name: 'getEthBalance',
+    outputs: [{ name: 'balance', type: 'uint256' }],
+    payable: false,
+    stateMutability: 'view',
+    type: 'function',
+  },
+  {
+    constant: true,
+    inputs: [],
+    name: 'getCurrentBlockDifficulty',
+    outputs: [{ name: 'difficulty', type: 'uint256' }],
+    payable: false,
+    stateMutability: 'view',
+    type: 'function',
+  },
+  {
+    constant: true,
+    inputs: [],
+    name: 'getCurrentBlockGasLimit',
+    outputs: [{ name: 'gaslimit', type: 'uint256' }],
+    payable: false,
+    stateMutability: 'view',
+    type: 'function',
+  },
+  {
+    constant: true,
+    inputs: [],
+    name: 'getCurrentBlockCoinbase',
+    outputs: [{ name: 'coinbase', type: 'address' }],
+    payable: false,
+    stateMutability: 'view',
+    type: 'function',
+  },
+  {
+    constant: true,
+    inputs: [{ name: 'blockNumber', type: 'uint256' }],
+    name: 'getBlockHash',
+    outputs: [{ name: 'blockHash', type: 'bytes32' }],
+    payable: false,
+    stateMutability: 'view',
+    type: 'function',
+  },
+];

packages/core/src/multicall.ts

@@ -6,7 +6,7 @@ import {
 import { Web3Provider } from '@ethersproject/providers';
 import { Contract, utils } from 'ethers';
 
-import MulticallAbi from './abi/Multicall.json';
+import { MulticallAbi } from './multiCallAbi.js';
 import type { Eip1193Provider, FeeHandlerType, RouteIndexerType } from './types.js';
 
 enum MulticallDeployedNetworks {