chore(deps): update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/build-docker-image.yml

@@ -21,7 +21,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Log in to the Container registry
         uses: docker/login-action@v3

.github/workflows/test.yml

@@ -8,7 +8,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup Node.js 20
         uses: actions/setup-node@v4