Bump actions/checkout from 2 to 4 (#247)

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -17,7 +17,7 @@ jobs:
       id-token: write
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
 
       - uses: actions/setup-node@v4
         with: