ci: Update checkout action

Author: maicol07

.github/workflows/tests.yml

@@ -24,7 +24,7 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
       - name: Get composer cache directory
         id: composer-cache
         run: echo "dir=$(composer config cache-files-dir)" >> $GITHUB_OUTPUT