Update actions/checkout digest to df4cb1c (#87)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/ci.yaml

@@ -22,7 +22,7 @@ jobs:
     name: Format
     runs-on: ubicloud-standard-2
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
 
       - name: Setup Python
         uses: ./.github/actions/setup-python
@@ -42,7 +42,7 @@ jobs:
     name: Lint
     runs-on: ubicloud-standard-2
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
 
       - name: Setup Python
         uses: ./.github/actions/setup-python
@@ -62,7 +62,7 @@ jobs:
     name: Type Check
     runs-on: ubicloud-standard-2
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
 
       - name: Setup Python
         uses: ./.github/actions/setup-python
@@ -88,7 +88,7 @@ jobs:
       contents: read
 
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
 
       - name: Setup Python
         uses: ./.github/actions/setup-python
@@ -141,7 +141,7 @@ jobs:
       packages: write
     steps:
       - name: Checkout code
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
 
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@d7f5e7f509e45cec5c76c4d5afdd7de93d0b3df5 # v4
@@ -190,7 +190,7 @@ jobs:
     if: ${{ github.event_name == 'push' || github.event_name == 'workflow_dispatch' }}
     steps:
       - name: Checkout code
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
 
       - name: Setup Fly.io CLI
         uses: superfly/flyctl-actions/setup-flyctl@63da3ecc5e2793b98a3f2519b3d75d4f4c11cec2