ci: update checkout action

Author: valentin-vogel

.github/workflows/lint.yml

@@ -6,7 +6,7 @@ jobs:
     name: "lint: awesome-lint"
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0
       - run: npx awesome-lint