Update actions/checkout@v4

Author: danon

.github/workflows/build.yaml

@@ -45,7 +45,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Use PHP ${{ matrix.php-version }}
         uses: shivammathur/setup-php@v2