Merge pull request #30 from fumito-ito/renovate/actions-checkout-4.x

Update actions/checkout action to v4

Author: fumito-ito

.github/workflows/swift.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: macos-14
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Install swiftlint
       run: |
         brew update