chore(deps): update actions/checkout action to v4

Author: renovate[bot]

.github/workflows/ci.yml

@@ -8,10 +8,10 @@ jobs:
     name: Lint (dummy)
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
 
   test:
     name: Test (dummy)
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4