Update pragma to 0.8.20 (#4489)

Co-authored-by: Francisco Giordano <fg@frang.io>
Co-authored-by: ernestognw <ernestognw@gmail.com>

scripts/generate/templates/Checkpoints.js

@@ -3,7 +3,7 @@ const { OPTS } = require('./Checkpoints.opts.js');
 
 // TEMPLATE
 const header = `\
-pragma solidity ^0.8.19;
+pragma solidity ^0.8.20;
 
 import {Math} from "../math/Math.sol";
 

scripts/generate/templates/Checkpoints.t.js

@@ -4,7 +4,7 @@ const { OPTS } = require('./Checkpoints.opts.js');
 
 // TEMPLATE
 const header = `\
-pragma solidity ^0.8.19;
+pragma solidity ^0.8.20;
 
 import {Test} from "forge-std/Test.sol";
 import {SafeCast} from "../../../contracts/utils/math/SafeCast.sol";

scripts/generate/templates/EnumerableMap.js

@@ -10,7 +10,7 @@ const TYPES = [
 
 /* eslint-disable max-len */
 const header = `\
-pragma solidity ^0.8.19;
+pragma solidity ^0.8.20;
 
 import {EnumerableSet} from "./EnumerableSet.sol";
 

scripts/generate/templates/EnumerableSet.js

@@ -9,7 +9,7 @@ const TYPES = [
 
 /* eslint-disable max-len */
 const header = `\
-pragma solidity ^0.8.19;
+pragma solidity ^0.8.20;
 
 /**
  * @dev Library for managing

scripts/generate/templates/SafeCast.js

@@ -4,7 +4,7 @@ const { range } = require('../../helpers');
 const LENGTHS = range(8, 256, 8).reverse(); // 248 → 8 (in steps of 8)
 
 const header = `\
-pragma solidity ^0.8.19;
+pragma solidity ^0.8.20;
 
 /**
  * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow

scripts/generate/templates/StorageSlot.js

@@ -11,7 +11,7 @@ const TYPES = [
 ].map(type => Object.assign(type, { struct: (type.name ?? capitalize(type.type)) + 'Slot' }));
 
 const header = `\
-pragma solidity ^0.8.19;
+pragma solidity ^0.8.20;
 
 /**
  * @dev Library for reading and writing primitive types to specific storage slots.