chore: upgrade actions/checkout

Author: tu6ge

.github/workflows/ci.yml

@@ -19,7 +19,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Install system dependencies (gpui)
         run: |