update CI configuration

Author: ivailop

.github/workflows/ci.yml

@@ -13,7 +13,7 @@ jobs:
           php-version: 7.4
           extensions: sqlite
           tools: composer, phpcs, phpmd, phpunit
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: testspace-com/setup-testspace@v1
         with:
           domain: samples