Bump actions/checkout from 5 to 6 (#110)

Author: dependabot[bot]

.github/workflows/build.yml

@@ -21,7 +21,7 @@ jobs:
     steps:
       # Checks-out your repository under $GITHUB_WORKSPACE
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           # The GitHub token is preserved by default but this job doesn't need
           # to be able to push to GitHub.