remove default smart contracts

src/Counter.sol

@@ -1,14 +0,0 @@
-// SPDX-License-Identifier: UNLICENSED
-pragma solidity ^0.8.13;
-
-contract Counter {
-    uint256 public number;
-
-    function setNumber(uint256 newNumber) public {
-        number = newNumber;
-    }
-
-    function increment() public {
-        number++;
-    }
-}