Update actions/checkout action to v4

Author: renovate[bot]

.github/workflows/lint.yml

@@ -6,7 +6,7 @@ jobs:
   renovate:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: 🧼 lint renovate config # Validates changes to renovate.json config file
         uses: suzuki-shunsuke/github-action-renovate-config-validator@v0.1.2
         with:

.github/workflows/php.yml

@@ -17,7 +17,7 @@ jobs:
     name: PHP ${{ matrix.php-versions }} Test on ${{ matrix.operating-system }}
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
       - name: Install PHP
         uses: shivammathur/setup-php@v2
         with: