Add toUint, toInt and hexToUint to Strings (#5166)

Co-authored-by: cairo <cairoeth@protonmail.com>
Co-authored-by: Ernesto García <ernestognw@gmail.com>

test/utils/Strings.t.sol

@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+import {Test} from "forge-std/Test.sol";
+
+import {Strings} from "@openzeppelin/contracts/utils/Strings.sol";
+
+contract StringsTest is Test {
+    using Strings for *;
+
+    function testParse(uint256 value) external {
+        assertEq(value, value.toString().parseUint());
+    }
+
+    function testParseSigned(int256 value) external {
+        assertEq(value, value.toStringSigned().parseInt());
+    }
+
+    function testParseHex(uint256 value) external {
+        assertEq(value, value.toHexString().parseHexUint());
+    }
+
+    function testParseChecksumHex(address value) external {
+        assertEq(value, value.toChecksumHexString().parseAddress());
+    }
+}