chore(deps): update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/ci.yml

@@ -11,7 +11,7 @@ jobs:
         node-version: [18.x, 20.x]
 
     steps:
-      - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
       - name: Use Node.js ${{ matrix.node-version }}
         uses: actions/setup-node@v4
         with: