Update GitHub Actions to use checkout@v5 for Node.js 24 support

Author: ajaydsouza

.github/workflows/unit-tests.yml

@@ -40,7 +40,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Setup MySQL
         uses: ankane/setup-mysql@v1