remove Counter contract and add basic Raffle contract

lottery/script/Counter.s.sol

@@ -1,19 +0,0 @@
-// SPDX-License-Identifier: UNLICENSED
-pragma solidity ^0.8.13;
-
-import {Script, console} from "forge-std/Script.sol";
-import {Counter} from "../src/Counter.sol";
-
-contract CounterScript is Script {
-    Counter public counter;
-
-    function setUp() public {}
-
-    function run() public {
-        vm.startBroadcast();
-
-        counter = new Counter();
-
-        vm.stopBroadcast();
-    }
-}