⬆️ upgrade actions/checkout action to v6

Author: renovate[bot]

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ jobs:
 
     steps:
       - name: Checkout repo
-        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4
+        uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6
 
       - name: Use Node
         uses: actions/setup-node@v4