Bump actions/checkout from 5.0.0 to 6.0.0 (exercism#352)

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3
       - run: docker pull exercism/sml-test-runner
       - name: Run tests for all exercises
         run: sh ./bin/test