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

Author: renovate[bot]

.github/workflows/main.yml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Setup Node.js
         uses: actions/setup-node@v6

.github/workflows/pr.yml

@@ -18,7 +18,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
           repository: ${{ github.event.pull_request.head.repo.full_name }}
@@ -62,7 +62,7 @@ jobs:
       pull-requests: write
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         if: ${{ github.event.action != 'closed' }}
         with:
           repository: ${{ github.event.pull_request.head.repo.full_name }}